On Sun, 03 Feb 2019 18:16:02 +0000 (GMT), charles
wrote:

In article ,
Archibald Tarquin Blenkinsopp wrote:
On Sun, 3 Feb 2019 17:19:27 -0000, "Mark" wrote:


"Tim+" wrote in message
...


Of course these kits arent actually teaching me anything

I started off with books from Babani press 50 circuits using
transistors -zener diodes- 741 - 555ic timers etc
in fact the burglar alarm on the workshop is still going and made in the 70s
from the books


On the same battery no doubt?

The current through anything made from Babani books must be quite low
:-)


I too relied on those, but some time later when I went into industrial
electronics, I found that manufacturers application notes were far
better and well subsidised too. They had all manner of circuits
developed around their components with a liberal sprinkling of test
data and maths also.

I often thought of writing a few articles for the electronics comics
based on my databooks.

https://archive.org/details/National...andbook1994OCR

Enjoy!

If you use NS databooks to make a circuit, I would reccomend a soak in
a strong saline solution first though :-)

AB



I've still got my copy of "Mullard - Transistors for the Experimenter"
(rather battered) and Mullard -Reference Manual of Transistor Circuits"
as well as some "Marston - 110 _____ circuits"

A dammned brilliant company, when Britain did lead the world in
technology and engineering.

It didn't last long though :-(


I had the Mullard 5/10 book, never did build the 5/10, but I did knock
out a few smaller class "A" lashups using the values from the book.

I think the EF86 was for magnetic pickups anyway. My meager funds only
stretched to a crystal cartridge, so I could almost drive the output
directly.

AB

presented the following explanation :
The tolerance band always goes to the front or right. Neater that way and
easier to read the values.

That is how I always built PCB's up, so much tidier.

After serious thinking Bob Eager wrote :
I made a clone of my friend's Heathkit amplifer; used it for years.

Then I actually bought a Heathkit stereo amplifier and a tuner. Used
those for a long time too.

I built an early 60's Sinclair amp into a record deck I was building
up.

Terry Casey expressed precisely :
The American Radio History site is a goldmine that contains
thousands of magazines with a lot of constructional projects
in them including PW, PE, PT, RC & WW from the UK as well as
Elektor and the Maplin publications already mentioned.

Maybe you will find some of my submissions in there..

On 03/02/2019 15:31, Archibald Tarquin Blenkinsopp wrote:
On Sun, 3 Feb 2019 14:38:45 +0000, John Rumm
wrote:

On 03/02/2019 09:58, Tim+ wrote:

Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

I would say look out for a collection of old electronics mags...
something like the Maplin mag used to publish loads of projects for
which they supplied kits, but crucially also published the PCB layouts
etc, so even with the demise of Maplin they should sill be buildable.

Are you for real?

last time I looked yup...

Someone getting into electronics, PCB kits?

Many of the old Maplin kits had full schematic, and a good description
of the operation of the circuit. So there was plenty of opportunity to
learn a bit as you went along.

I really do get sick of people that know damn all trying to give
advice on this NG.

And yet you still do it?

PCB manufacture is a subject in itself, for amateur use it is only
employed after the CCT has been built and tested, even then it is
pointless, as the "breadboarding" on Veroboard or similar will be
perfectly functional and can be as neat as a PCB.

Sure, I was not suggesting it was not. However if you have an
electronics mag that has a project that includes a custom PCB layout,
that does not stop you building the project. You either relay it on
veroboard etc, or make (or have made) the PCB.

DIY PCB manufacturing of the type of thing you will find in that era of
mag is easy. Typically single layer. Get a decent copy of the layout
onto a transparency, UV expose a board with a photo resist coating and
away you go.

However for many projects you don't need a custom PCB anyway.

Supplied kits are able to use a PCB, simply because the dimensions of
the components are known, they have been bought in bulk.

There are hundreds or even thousands of these circuits built, so a PCB
is a cost effective approach. Buying parts from other suppliers will
invariably lead to holes and spaces that dont accommodate the wires or
components.

On a final note, if you have a female in the house, trays of ferric
are about as popular as a beer fuelled rugby reunion.

Yeah well the female in this house is a engineering graduate who still
likes to remind me she scored higher than me on digital circuit design!

Actually a decent ziploc bag is not a bad way of doing etching. Keeps it
mostly self contained.

If you don't fancy doing your own boards (and for anything modern with
plated through vias or more than two layers there is not much point),
then there are plenty of places that will make boards relatively cheaply
if you send them a layout.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 03/02/2019 11:20, Brian Gaff wrote:
Well sadly one thing I did notice before I lost too much sight was that
these kits were getting less and less technical as the chips concerned did
most of the grunt work and nobody seemed to worry quite how they did so!
I remember putting together the zX81 and that nearly gave me repetitive
strain injury due to the number of diodes and resistors which had all the
same values and alignments!

Brian


Did you keep the 16K dynamic ram board cool with a carton of milk ?

Archibald Tarquin Blenkinsopp wrote:

On Sun, 3 Feb 2019 17:19:27 -0000, "Mark" wrote:


"Tim+" wrote in message
...


Of course these kits arent actually teaching me anything

I started off with books from Babani press 50 circuits using
transistors -zener diodes- 741 - 555ic timers etc
in fact the burglar alarm on the workshop is still going and made in the 70s
from the books


On the same battery no doubt?

The current through anything made from Babani books must be quite low
:-)


I too relied on those, but some time later when I went into industrial
electronics, I found that manufacturers application notes were far
better and well subsidised too. They had all manner of circuits

well yes but in the 70s no access to them or an internet
and the Babani books explained how and why the components and circuit worked
all very simple stuff but invaluable start to electronics
the first thing I ever built was a intermittent windscreen wiper control for an Austin Cambridge ;(

-

On Sun, 3 Feb 2019 23:37:11 -0000 (UTC), Mark wrote:

Archibald Tarquin Blenkinsopp wrote:

On Sun, 3 Feb 2019 17:19:27 -0000, "Mark" wrote:


"Tim+" wrote in message
...


Of course these kits arent actually teaching me anything

I started off with books from Babani press 50 circuits using
transistors -zener diodes- 741 - 555ic timers etc
in fact the burglar alarm on the workshop is still going and made in the 70s
from the books


On the same battery no doubt?

The current through anything made from Babani books must be quite low
:-)


I too relied on those, but some time later when I went into industrial
electronics, I found that manufacturers application notes were far
better and well subsidised too. They had all manner of circuits

well yes but in the 70s no access to them or an internet
and the Babani books explained how and why the components and circuit worked
all very simple stuff but invaluable start to electronics
the first thing I ever built was a intermittent windscreen wiper control for an Austin Cambridge ;(

-
I put together a Praccy Electronics one using an SCR and a few other
components.

I didn't have a car at the time :-(

I gave it away, but the recipient couldn't get it to work. Not sure if
it was the recipient or the circuit that was the problem, but I went
on to build far more complex none working projects :-)


AB

On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:
Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Tim

Small Tesla coils are useful if you can adjust the output power.

Other than that I'd look at non-kits, ie projects described online.


NT

On Sun, 3 Feb 2019 20:56:46 -0800 (PST), wrote:

On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:
Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so I’m keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits aren’t actually teaching me anything (other than
soldering skills) and I’d like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that won’t break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Tim

Small Tesla coils are useful if you can adjust the output power.

?????

Go on, what the hell would you want to limit the wallymitts for,
mobile phone charging?

Unless you are setting up in a sauna, I was of the impression that the
main practical use of Tesla coils was to impress the youtube
fraternity without the expense of "lighting the blue touch paper".

AB

On Monday, 4 February 2019 06:56:33 UTC, Archibald Tarquin Blenkinsopp wrote:
On Sun, 3 Feb 2019 20:56:46 -0800 (PST), tabbypurr wrote:
On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:

Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Tim

Small Tesla coils are useful if you can adjust the output power.

?????

Go on, what the hell would you want to limit the wallymitts for,
mobile phone charging?

Unless you are setting up in a sauna, I was of the impression that the
main practical use of Tesla coils was to impress the youtube
fraternity without the expense of "lighting the blue touch paper".

AB

It isn't sense day for you is it.

Actually they used to be sold as violet wands and all sorts of pseudo
health clamed were made about running then over the bare skin. Soon the
fetishists were using them as sensual toys as well. A good working vintage
one is still worth quite a lot of money I gather.
However one does need to be a little careful about sparking, burning and
ozone generation in a poorly ventilated area.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
On Monday, 4 February 2019 06:56:33 UTC, Archibald Tarquin Blenkinsopp
wrote:
On Sun, 3 Feb 2019 20:56:46 -0800 (PST), tabbypurr wrote:
On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:

Having watched too many Big Clive videos I decided to have a go at a
simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so I'm
keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits aren't actually teaching me anything (other than
soldering skills) and I'd like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that won't
break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Tim

Small Tesla coils are useful if you can adjust the output power.

?????

Go on, what the hell would you want to limit the wallymitts for,
mobile phone charging?

Unless you are setting up in a sauna, I was of the impression that the
main practical use of Tesla coils was to impress the youtube
fraternity without the expense of "lighting the blue touch paper".

AB

It isn't sense day for you is it.

In article ,
says...


I think the EF86 was for magnetic pickups anyway.

How do you work that out? The Mullard 5-10 and the 3-3 (amonst
others) were ideal for use with a crystal cartridge.

You'd need a pre-amp for use with a magnetic one!

Why not refresh your memory?

http://www.r-type.org/articles/art-003e.htm

--

Terry

---
This email has been checked for viruses by AVG.
https://www.avg.com

In article
,
says...

DIY PCB manufacturing of the type of thing you will find in that era of
mag is easy. Typically single layer. Get a decent copy of the layout
onto a transparency, UV expose a board with a photo resist coating and
away you go.


OK if you've got the UV unit.

I used to do mine completely manually. If a full size layout
wasn't available, draw it out on 0.1" squared graph paper them
temporarilly wrap it round the board and tape on the non-foil
side.

Go round with a sharp scriber to transfer the hole positions
to the board, then very carefully draw the tracks on the foil
using nail varnish - something dark to show up well on the
polished copper.

Etch then remove the varnish with acetone.

Time consuming, of course, but there was always a very
satisfied feeling when you could hold the finished article in
your hand!

Usually a much more compacr result that possible with other
construction methods, particularly if the inter-strip
capacitance of Veroboard ruled out that method for the
particular application.

--

Terry

---
This email has been checked for viruses by AVG.
https://www.avg.com

On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:
Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Kits are all very well but will you actually learn anything from putting together a kit, well a bit perhaps.

We run a skills course to get our students up to speed on the more practicel side of things and use this book picking out certain experiments and telling them to do them.

https://www.amazon.co.uk/Make-Electr...ha rles+platt


It's not bad I've been suggesting the 'department' should write its own version but no one seems really interested.

I do have a copy of the previous version as a PDF you could borrow, of course then you'll go and order the second edition above :-}

On Monday, 4 February 2019 11:46:12 UTC, Terry Casey wrote:
In article
,
says...

DIY PCB manufacturing of the type of thing you will find in that era of
mag is easy. Typically single layer. Get a decent copy of the layout
onto a transparency, UV expose a board with a photo resist coating and
away you go.


OK if you've got the UV unit.

There can't be many folk here that don't have access to the sky


NT

whisky-dave wrote:
On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:
Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Kits are all very well but will you actually learn anything from putting
together a kit, well a bit perhaps.

Well yeah, I do recognise that.


We run a skills course to get our students up to speed on the more
practicel side of things and use this book picking out certain
experiments and telling them to do them.

https://www.amazon.co.uk/Make-Electr...ha rles+platt


It's not bad I've been suggesting the 'department' should write its own
version but no one seems really interested.

I do have a copy of the previous version as a PDF you could borrow, of
course then you'll go and order the second edition above :-}

Couldnt wait. Just ordered the book. ;-)

Thanks for the heads up.

Tim

--
Please don't feed the trolls

In article ,
wrote:
On Monday, 4 February 2019 11:46:12 UTC, Terry Casey wrote:
In article
,
says...

DIY PCB manufacturing of the type of thing you will find in that era of
mag is easy. Typically single layer. Get a decent copy of the layout
onto a transparency, UV expose a board with a photo resist coating and
away you go.


OK if you've got the UV unit.

There can't be many folk here that don't have access to the sky


Hmm. I've made a fair few PCBs over the years, and both the quality of the
blacks on the transparency and the exposure time with a pukka UV box are
critical. And then my printer broke, and the new one didn't give as good a
black for stopping the UV - dunno if it was different ink. And my cheap
B&W laser, useless.

--
*IF ONE SYNCHRONIZED SWIMMER DROWNS, DO THE REST DROWN TOO?

Dave Plowman London SW
To e-mail, change noise into sound.

I recall reading somewhere that using a laser printer on old glossy magazine pages allows you to transfer the print directly onto plain copper clad board by applying heat with a domestic iron. (As long as SWAMBO does not find out). I think it was on one of the maker sites.

Never tried it myself having till recently had access to a UV box and Tri Tank etcher. I agree that the timing of the UV exposure is critical but the concentration of the developer is what we found most problems with which rapidly degraded unless kept in an air-tight container.

Richard

In article ,
Tricky Dicky wrote:
I recall reading somewhere that using a laser printer on old glossy
magazine pages allows you to transfer the print directly onto plain
copper clad board by applying heat with a domestic iron. (As long as
SWAMBO does not find out). I think it was on one of the maker sites.

Never tried it myself having till recently had access to a UV box and
Tri Tank etcher. I agree that the timing of the UV exposure is critical
but the concentration of the developer is what we found most problems
with which rapidly degraded unless kept in an air-tight container.

You can buy sheets of stuff you print to then iron on to the PCB. Never
had much success with them either.

Those who say the whole process simple haven't ever done it, IMHO.

--
*Work is for people who don't know how to fish.

Dave Plowman London SW
To e-mail, change noise into sound.

explained :
On Monday, 4 February 2019 07:56:22 UTC, Brian Gaff wrote:
tabbypurr wrote in message
...
On Monday, 4 February 2019 06:56:33 UTC, Archibald Tarquin Blenkinsopp
wrote:
On Sun, 3 Feb 2019 20:56:46 -0800 (PST), tabbypurr wrote:
On Sunday, 3 February 2019 09:58:11 UTC, Tim+ wrote:
Having watched too many Big Clive videos I decided to have a go at a
simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so I'm
keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits aren't actually teaching me anything (other than
soldering skills) and I'd like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that won't
break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Tim

Small Tesla coils are useful if you can adjust the output power.

?????

Go on, what the hell would you want to limit the wallymitts for,
mobile phone charging?

Unless you are setting up in a sauna, I was of the impression that the
main practical use of Tesla coils was to impress the youtube
fraternity without the expense of "lighting the blue touch paper".

AB

It isn't sense day for you is it.

Actually they used to be sold as violet wands and all sorts of pseudo
health clamed were made about running then over the bare skin. Soon the
fetishists were using them as sensual toys as well. A good working vintage
one is still worth quite a lot of money I gather.
However one does need to be a little careful about sparking, burning and
ozone generation in a poorly ventilated area.
Brian

The '51 court case concluded they were quack devices on the ground that no
study was brought forth proving their effectiveness. However this was a
fundamentally flawed conclusion. When violet rays were introduced at the turn
of the century, it was not normal to conduct any studies into effectiveness
or toxicity before releasing a new medical product, if it worked for a couple
of people the manufacturer tried selling it, and that was all there was to
it. Once any patent period expired, a drug or machine was then impractical to
do such a study on, as the studies are expensive and there would be no means
to recoup the costs. Any such study would simply be a recipe for bankruptcy.
Thus no formal study could reasonably be expected.

There's a lot more to the story. Suffice it to say I found a lot of people
for whom a VR resolved various conditions and I tried one. It is very
effective for what I've tried it for - I've no experience of its use on the
other conditions the early manuals discussed.

Sparking, burning & ozone are not a problem. Their widespread use by
physicians in the 1920s & 30s found them to be extremely safe.


NT

I have vague recollections of some sort of high voltage discharge being
used on me, to promote a bone fracture repair. This was in the 1960's,
in hospital as an out patient, a fractured left arm.

On Monday, 4 February 2019 15:41:17 UTC, Dave Plowman (News) wrote:
In article ,
Tricky Dicky wrote:

I recall reading somewhere that using a laser printer on old glossy
magazine pages allows you to transfer the print directly onto plain
copper clad board by applying heat with a domestic iron. (As long as
SWAMBO does not find out). I think it was on one of the maker sites.

Never tried it myself having till recently had access to a UV box and
Tri Tank etcher. I agree that the timing of the UV exposure is critical
but the concentration of the developer is what we found most problems
with which rapidly degraded unless kept in an air-tight container.

You can buy sheets of stuff you print to then iron on to the PCB. Never
had much success with them either.

Those who say the whole process simple haven't ever done it, IMHO.

I've made loads of PCBs, and it is fairly simple imho. I used a uv light box, but did try skylight at least once. For beginners & simple projects I'd suggest either stripboard or pad board, you can look at PCB production & its pitfalls later. You can of course also make PCBs with just a dremel.


NT

Terry Casey explained :
Usually a much more compacr result that possible with other
construction methods, particularly if the inter-strip
capacitance of Veroboard ruled out that method for the
particular application.

For the more complex stuff, I used a system rather like a wire wrap
system. It used a fine enamelled wire from a plastic pen, and plastic
combs to control the wire on the board. You simply wrapped around a IC
pin, then hooked onto the comb, to you next pin and so on, then you
soldered. It allowed some fairly complex stuff to be built, providing
cross-talk or capacitance between wires wouldn't a problem. It used the
Veroboard with tiny copy patches at the holes, or Veroboard prototyping
boards. You could also make connections to tiny pins which were a tight
fit to the Veroboard holes. It was very easy to make up memory boards
on Euro size boards.

In article ,
wrote:
I've made loads of PCBs, and it is fairly simple imho. I used a uv light
box, but did try skylight at least once. For beginners & simple projects
I'd suggest either stripboard or pad board, you can look at PCB
production & its pitfalls later. You can of course also make PCBs with
just a dremel.

You can (or could) get etch resistant pens. Draw the circuit on the
copper, then etch in the normal way. That was the earliest method I
remember.

--
*What boots up must come down *

Dave Plowman London SW
To e-mail, change noise into sound.

On 04/02/2019 15:24, Tricky Dicky wrote:
I recall reading somewhere that using a laser printer on old glossy magazine pages allows you to transfer the print directly onto plain copper clad board by applying heat with a domestic iron. (As long as SWAMBO does not find out). I think it was on one of the maker sites.

I have a spare domestic iron that I use for work with veneers - doesn't
everybody?


Never tried it myself having till recently had access to a UV box and Tri Tank etcher. I agree that the timing of the UV exposure is critical but the concentration of the developer is what we found most problems with which rapidly degraded unless kept in an air-tight container.

I only used to make simple, one-off boards so never tried a photo
technique: I used to paint the resist onto the copper before dunking the
board into the etching tank.


Nick

In article ,
says...


You can (or could) get etch resistant pens. Draw the circuit on the
copper, then etch in the normal way. That was the earliest method I
remember.

I think I'd made quite a few PCBs before they came along, so I
stuck to the nail varnish with its need applicator brush and
mixing ball in the same container!

My first attempts used candle wax on the board which I melted
and smoothed over with the barrel of my 25W Henley Solon
soldering iron but gave up after two attempts as the element
failed after both of them!

I just scratched through the wax to the bare board and used
concentrated nitric acid applied with a glass dropper to etch
it - outdoors, of course!

(A school friend who was heavily into chemistry was on good
terms with a local chemist and got the acid for me!)

--

Terry

---
This email has been checked for viruses by AVG.
https://www.avg.com

On 03/02/2019 09:58, Tim+ wrote:

Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Depends what you are interested in. EPE still does the odd basic project
that isn't just a single chip and its application note.

If you want to start at a nuts and bolts level with basic transistor
circuits then ISTR there is an EPE Electronics for beginners or if you
want something a little more challenging you can learn most of the
basics about classic bipolar transistor circuit designs from Ferranti's
classic E line Transistor Applications (free online) at:

https://archive.org/details/Ferranti...orApplications

Unlike Wireless World project circuit diagrams of old most of the
designs in that handbook actually work as described.

--
Regards,
Martin Brown

In article ,
Nick Odell wrote:
I only used to make simple, one-off boards so never tried a photo
technique: I used to paint the resist onto the copper before dunking the
board into the etching tank.

Photo method helps when you're no good at freehand drawing. ;-)

--
*Any connection between your reality and mine is purely coincidental

Dave Plowman London SW
To e-mail, change noise into sound.

On Mon, 4 Feb 2019 11:29:29 -0000, Terry Casey
wrote:

In article ,
says...


I think the EF86 was for magnetic pickups anyway.

How do you work that out? The Mullard 5-10 and the 3-3 (amonst
others) were ideal for use with a crystal cartridge.

You'd need a pre-amp for use with a magnetic one!

Why not refresh your memory?

http://www.r-type.org/articles/art-003e.htm

You are quite correct. The component values would be tailored for a
high impedance.

The shock and horror, a poxy crystal cartridge feeding a Mullard 5/10.

Here was I thinking it was Shure V15 material :-(

Thanks for the enlightenment and the circuit of course.

AB

On 04/02/2019 16:57, Dave Plowman (News) wrote:
In article ,
wrote:
I've made loads of PCBs, and it is fairly simple imho. I used a uv light
box, but did try skylight at least once. For beginners & simple projects
I'd suggest either stripboard or pad board, you can look at PCB
production & its pitfalls later. You can of course also make PCBs with
just a dremel.

You can (or could) get etch resistant pens. Draw the circuit on the
copper, then etch in the normal way. That was the earliest method I
remember.

Next step up being layout rub down transfers... makes laying out DIP
pads etc much quicker. You can either use them direct on a board as an
etch resist layout, or on acetate to make a photo etch template.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 04/02/2019 15:55, Harry Bloomfield wrote:
Terry Casey explained :
Usually a much more compacr result that possible with other
construction methods, particularly if the inter-strip
capacitance of Veroboard ruled out that method for the
particular application.

For the more complex stuff, I used a system rather like a wire wrap
system. It used a fine enamelled wire from a plastic pen, and plastic
combs to control the wire on the board. You simply wrapped around a IC
pin, then hooked onto the comb, to you next pin and so on, then you
soldered. It allowed some fairly complex stuff to be built, providing
cross-talk or capacitance between wires wouldn't a problem. It used the
Veroboard with tiny copy patches at the holes, or Veroboard prototyping
boards. You could also make connections to tiny pins which were a tight
fit to the Veroboard holes. It was very easy to make up memory boards on
Euro size boards.

Sounds like a verowire pen... I still have one I bought decades ago.
Never used it much it has to be said.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Archibald Tarquin Blenkinsopp wrote:
Someone getting into electronics, PCB kits?

I really do get sick of people that know damn all trying to give
advice on this NG.

PCB manufacture is a subject in itself, for amateur use it is only
employed after the CCT has been built and tested, even then it is
pointless, as the "breadboarding" on Veroboard or similar will be
perfectly functional and can be as neat as a PCB.

If you a design, a PCB is $2 delivered from China:
https://jlcpcb.com/

The main issue with an old magazine is that you don't have gerbers to send
to the fab, you'd have to do some awkward scanning and image processing to
make them.

But if you have the files and can wait a month for the slow boat it's pretty
cheap and easy these days.

Theo

In article ,
Archibald Tarquin Blenkinsopp writes:
On Sun, 3 Feb 2019 14:38:45 +0000, John Rumm
wrote:

On 03/02/2019 09:58, Tim+ wrote:

Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so I’m keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits aren’t actually teaching me anything (other than
soldering skills) and I’d like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that won’t break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

I would say look out for a collection of old electronics mags...
something like the Maplin mag used to publish loads of projects for
which they supplied kits, but crucially also published the PCB layouts
etc, so even with the demise of Maplin they should sill be buildable.

I still notionally have all the electronics magazines I
bought (or my dad bought for me in many cases) since 1972.
Mostly Everyday Electronics, Practical Electronics,
ETI (Electronics Today International), Elektor, Electronics
and Music Maker (was a Maplin publication). Also a few
Practical Wireless if it had something of particular interest.

Elektor is still going, and I think a merger of Everyday
Electronics and Practical Electronics might still be going,
although I don't buy them anymore. Elektor sell PCBs for
their projects, and in some cases complete kits and/or carry
adverts for them from other people.

Are you for real?

Someone getting into electronics, PCB kits?

I really do get sick of people that know damn all trying to give
advice on this NG.

Wow

PCB manufacture is a subject in itself, for amateur use it is only
employed after the CCT has been built and tested, even then it is
pointless, as the "breadboarding" on Veroboard or similar will be
perfectly functional and can be as neat as a PCB.

That does make surface mount difficult, and some components nowadays
are only available surface mount, sadly. Having said that, I have
used them on veroboard, but you really need to be extremely good at
soldering for this to work.

Supplied kits are able to use a PCB, simply because the dimensions of
the components are known, they have been bought in bulk.

Nah - the PCB designs produced by the electronics magazines
were not that specific, and there's lots of flexibility in
discrete through-hole components. Boards can even have
footprints for multiple component choices where necessary.

There are hundreds or even thousands of these circuits built, so a PCB
is a cost effective approach. Buying parts from other suppliers will
invariably lead to holes and spaces that dont accommodate the wires or
components.

On a final note, if you have a female in the house, trays of ferric
are about as popular as a beer fuelled rugby reunion.

My board etching stuff is still in the garage with bottles of
unused and used ferric chloride which I used to buy from the
chemist (bet you can't do that anymore), but I haven't used them
20+ years.

Nowadays, I design my PCBs with KiCad and get them manufactured
from the gerber files, although I wouldn't have been able to afford
that as a teenager (even if it had been available at the time).

I do prototypes or one-offs usually on Tri-pad veroboard. This is
excellent for DIL chips and GPIO connectors, and also things that
don't fit this pattern. It used to be sold only by Maplin, made
for them by Vero. I now order it direct from Vero since Maplin
vanished. I was going to include the URL, but it's gone from their
website - I emailed Vero and that's a mistake they're fixing and
it's still stocked.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Tuesday, 5 February 2019 14:20:25 UTC, Andrew Gabriel wrote:



Elektor is still going,

I subscribe to it interesting sometimes .

https://www.elektor.com/



PCB manufacture is a subject in itself, for amateur use it is only
employed after the CCT has been built and tested, even then it is
pointless, as the "breadboarding" on Veroboard or similar will be
perfectly functional and can be as neat as a PCB.

That does make surface mount difficult, and some components nowadays
are only available surface mount, sadly.

yes I've noticed, you can get SOIC to DIP but they can be expensive sometimes far more than the chip itself. The real problems comes with the square packages which are almost impossible to prototype or hand solder, especailly when the pads are under the chip.


Having said that, I have
used them on veroboard, but you really need to be extremely good at
soldering for this to work.

Supplied kits are able to use a PCB, simply because the dimensions of
the components are known, they have been bought in bulk.

Nah - the PCB designs produced by the electronics magazines
were not that specific, and there's lots of flexibility in
discrete through-hole components. Boards can even have
footprints for multiple component choices where necessary.

But if you buy a kit the parts are usually the correct size.



Nowadays, I design my PCBs with KiCad and get them manufactured
from the gerber files, although I wouldn't have been able to afford
that as a teenager (even if it had been available at the time).

Yes those cost even put us off at uni. it's only really worth doing if yuo want loads of same tyoe of boards.


I do prototypes or one-offs usually on Tri-pad veroboard.

What's tri-pad board ? unless it;s just board with 3 holes conencted together , then another £ ......

we've used matrix board where each hole is surrounted by copper ready to solder a few students use that, and then there's matrix board that has just holes more like plug booard no copper.



This is
excellent for DIL chips and GPIO connectors, and also things that
don't fit this pattern. It used to be sold only by Maplin, made
for them by Vero. I now order it direct from Vero since Maplin
vanished. I was going to include the URL, but it's gone from their
website - I emailed Vero and that's a mistake they're fixing and
it's still stocked.

Our PCBs are made using a CNC machine to route out the copper.
LPKF S103
https://www.youtube.com/watch?v=MJr2aZRREmA

think it was about £10K then a comnpressor for another £3K.


I doubt it's an option for the hobbyist but it would be interesting to see if someone can design & make a system at a reasnable price, afterall it's similar to a 3D printer in the way it would function.

On Monday, February 4, 2019 at 6:29:17 PM UTC, Martin Brown wrote:
On 03/02/2019 09:58, Tim+ wrote:

Having watched too many Big Clive videos I decided to have a go at a simple
digital clock kit from eBay.

The result was fairly decent and I enjoyed all the soldering so Im keen to
have a go at a few more cheap kits for soldering practice.

Of course these kits arent actually teaching me anything (other than
soldering skills) and Id like to progress to understanding a bit more
about the design and function of components/circuits.

So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

Depends what you are interested in. EPE still does the odd basic project
that isn't just a single chip and its application note.

If you want to start at a nuts and bolts level with basic transistor
circuits then ISTR there is an EPE Electronics for beginners or if you
want something a little more challenging you can learn most of the
basics about classic bipolar transistor circuit designs from Ferranti's
classic E line Transistor Applications (free online) at:

https://archive.org/details/Ferranti...orApplications

Unlike Wireless World project circuit diagrams of old most of the
designs in that handbook actually work as described.

--
Regards,
Martin Brown

Hey, great link to the scan of the Ferranti book - I remember that myself. Thanks for that.

J^n

whisky-dave wrote:
On Tuesday, 5 February 2019 14:20:25 UTC, Andrew Gabriel wrote:

yes I've noticed, you can get SOIC to DIP but they can be expensive
sometimes far more than the chip itself. The real problems comes with the
square packages which are almost impossible to prototype or hand solder,
especailly when the pads are under the chip.

Not if you buy from our Chinese friends:
https://www.aliexpress.com/item/GREA...954112517.html
(and a million different variations on the same)

Square packages not a problem either:
https://www.aliexpress.com/item/0-8-...774086808.html
https://www.aliexpress.com/item/5PCS...516670532.html
(soldering with hot air and paste isn't too hard when you get used to it)

[PCBs]
Yes those cost even put us off at uni. it's only really worth doing if
yuo want loads of same tyoe of boards.

As I mentioned upthread, $2 for 10off 100x100mm 1.6mm thick, jlcpcb.com If
you pay the extra $20 for express shipping, they come in just over a week.
We have a batch system - once a week/fortnight/month, collect up all the
boards and send them as one order with express shipping.

(the $2 is a loss leader, when you start tweaking the parameters it gets a
bit more realistic but still insanely cheap - like $12 - for a stack of
boards)

You will have to have the argument with your accounts department about
paying by credit card, since the Chinese supplier is not going to give you a
credit account.

Our PCBs are made using a CNC machine to route out the copper.
LPKF S103
https://www.youtube.com/watch?v=MJr2aZRREmA

think it was about £10K then a comnpressor for another £3K.

We have one of those (Bungard CCD). It's a pain to set up, hopeless at
doing anything fine pitch, double sided is annoying, and you don't get
soldermask which is critical for surface mount soldering. It's not really
got used for very much, especially now you can get very high quality
boards from China for so little.

Theo

On Tuesday, 5 February 2019 19:19:43 UTC, Theo wrote:
whisky-dave wrote:
On Tuesday, 5 February 2019 14:20:25 UTC, Andrew Gabriel wrote:

yes I've noticed, you can get SOIC to DIP but they can be expensive
sometimes far more than the chip itself. The real problems comes with the
square packages which are almost impossible to prototype or hand solder,
especailly when the pads are under the chip.

Not if you buy from our Chinese friends:
https://www.aliexpress.com/item/GREA...954112517.html
(and a million different variations on the same)

Yes yuo can get them cheaper, but still more expensive than a 555 or 741 and you still have to solder them to the board without damage and get the pins for prototyping, and then uo to 2 months delivery.



Square packages not a problem either:
https://www.aliexpress.com/item/0-8-...774086808.html
https://www.aliexpress.com/item/5PCS...516670532.html
(soldering with hot air and paste isn't too hard when you get used to it)

but you need the equipment.



[PCBs]
Yes those cost even put us off at uni. it's only really worth doing if
yuo want loads of same tyoe of boards.

As I mentioned upthread, $2 for 10off 100x100mm 1.6mm thick, jlcpcb.com If
you pay the extra $20 for express shipping, they come in just over a week..
We have a batch system - once a week/fortnight/month, collect up all the
boards and send them as one order with express shipping.

(the $2 is a loss leader, when you start tweaking the parameters it gets a
bit more realistic but still insanely cheap - like $12 - for a stack of
boards)

It depends on the quanitiies.
anyone is more than welcone to try these comanies.


Our PCBs are made using a CNC machine to route out the copper.
LPKF S103
https://www.youtube.com/watch?v=MJr2aZRREmA

think it was about £10K then a comnpressor for another £3K.

We have one of those (Bungard CCD). It's a pain to set up, hopeless at
doing anything fine pitch, double sided is annoying, and you don't get
soldermask which is critical for surface mount soldering.

We haven't found that a problem.

It's not really
got used for very much, especially now you can get very high quality
boards from China for so little.

But not very convinet for us, once a student has produced their board the chances of is being correct is quite small, so it;s done within a day or too so they can corect their errors and try again, just one board at a time by several students.
This is far more inmortant for teaching than just hetting a board.




Theo

Tim+ wrote:
..
So, any recommendations for basic and more advanced kits that wont break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

I've seen that BitsBox has already been mentioned to source components but
I don't think that any one has mentioned

https://www.electronicsclub.info.

--
Nige Danton - Replace the obvious with g.m.a.i.l

On Fri, 8 Feb 2019 05:47:09 -0000 (UTC), Nige Danton
wrote:

Tim+ wrote:
.
So, any recommendations for basic and more advanced kits that won’t break
the bank? At the moment looking at a cheap Tesla coil kit on eBay.

I've seen that BitsBox has already been mentioned to source components but
I don't think that any one has mentioned

https://www.electronicsclub.info.


Not sure how things are going now, but a great source of bits was
radio rallies.

I used to go years back, when large numbers of amateurs could buy the
bits and put a tranceiver together quite easily.

They stopped being interesting when all the morons could do was
compare the number of knobs on the latest Kenwood.

There may still be a few people that cater for proper amateurs though.

Drayton Manor was one of the better ones.

https://rsgb.org/main/news/rallies/

AB

In article ,
says...

Not sure how things are going now, but a great source of bits was
radio rallies.


There may still be a few people that cater for proper amateurs though.

Drayton Manor was one of the better ones.

https://rsgb.org/main/news/rallies/


I would have thought that the desriptions of the various
rallies described in your RSCB link would answer that
question.

I'm sure I saw a youtube video report of one - possibly in
Kent, somewhere - which showed that there was a very large
selection of bits and pieces available.

--

Terry

---
This email has been checked for viruses by AVG.
https://www.avg.com