I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?

"John Blake" wrote in message
ups.com...
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?


I would have tried to source a replacement xtal cartridge, to be honest. The
output of a ceramic is lower than that of a xtal type by a factor of up to
10. Also, the impedance is significantly lower. If the old 'gram has a valve
amplifier, chances are, the cartridge is originally hooked virtually
straight to the grid. Are you in the UK ? I might have a NOS xtal cartridge
laying about that I could let you have. I'll have a look later.

Arfa

On Sun, 22 Jul 2007 12:25:55 GMT, "Arfa Daily"
wrote:


"John Blake" wrote in message
oups.com...
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?


I would have tried to source a replacement xtal cartridge, to be honest. The
output of a ceramic is lower than that of a xtal type by a factor of up to
10. Also, the impedance is significantly lower. If the old 'gram has a valve
amplifier, chances are, the cartridge is originally hooked virtually
straight to the grid. Are you in the UK ? I might have a NOS xtal cartridge
laying about that I could let you have. I'll have a look later.

Arfa

Yes, it is a valve amplifier and I am in the UK. Thanks for your
offer, I would be very grateful for a replacement xtal cartridge.

John

John Blake wrote in message
ups.com...
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?


I've dozens of these NOS , mono,
Sonotone cardridge + stylus LP/S & ASS LP
http://www.diversed.fsnet.co.uk/sonotone.jpg
my email address off the URL below

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

John Blake wrote:
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?

Have you tried simply connecting the channels in series without a network?
That's the usual way.
Martin(Stockport)

On Sun, 22 Jul 2007 14:59:10 +0100, "N Cook"
wrote:

John Blake wrote in message
oups.com...
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?


I've dozens of these NOS , mono,
Sonotone cardridge + stylus LP/S & ASS LP
http://www.diversed.fsnet.co.uk/sonotone.jpg
my email address off the URL below

Thanks. I hate to show my ignorance but what is "ASS LP"?

on Sun, 22 Jul 2007 15:21:02 +0100, "Martin Crossley"
wrote:

John Blake wrote:
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?

Have you tried simply connecting the channels in series without a network?
That's the usual way.
Martin(Stockport)

Thanks, I'll give it a try.

John Blake wrote in message
...
On Sun, 22 Jul 2007 14:59:10 +0100, "N Cook"
wrote:

John Blake wrote in message
oups.com...
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?


I've dozens of these NOS , mono,
Sonotone cardridge + stylus LP/S & ASS LP
http://www.diversed.fsnet.co.uk/sonotone.jpg
my email address off the URL below

Thanks. I hate to show my ignorance but what is "ASS LP"?



AFAIAA
Artificial Saphire Stylus and then long play or standard play

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

On 22 Jul, 14:59, "N Cook" wrote:

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list onhttp://home.graffiti.net/diverse:graffiti.net/

Unfortunately, a number of the links on this site crash my browser -
I've tried both Firefox and Internet Explorer. Any ideas?

On Jul 22, 9:24 pm, John Blake wrote:
on Sun, 22 Jul 2007 15:21:02 +0100, "Martin Crossley"

wrote:
John Blake wrote:
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.

Could anyone point me towards a web site or book or other source of a
suitable circuit please?

Have you tried simply connecting the channels in series without a network?
That's the usual way.
Martin(Stockport)

Thanks, I'll give it a try.

you probably need a BSR x5H cart which should give you about the same
output as the original and was a common replacement in the 70s when
those heavy crystal carts in old machines became incompatible when
stereo records appeared.

.. But do try what martin suggests.

have you tried posting on Paul stenning's uk vintage repair and
restoration site forum? what the guys there don't know about these
matters ain't worth knowing! ;-)
-B

In series? Don't you mean parallel?

b wrote:
On Jul 22, 9:24 pm, John Blake wrote:
on Sun, 22 Jul 2007 15:21:02 +0100, "Martin Crossley"

wrote:
John Blake wrote:
I have replaced the record player deck in an old radiogram, which had
a mono crystal cartridge, with a BSR deck with an SC12H ceramic
cartridge. I have used a simple resistive network to combine the two
channels but think I need an active interface as the sound is very
weak and there's a fair amount of hum.
Could anyone point me towards a web site or book or other source of a
suitable circuit please?
Have you tried simply connecting the channels in series without a network?
That's the usual way.
Martin(Stockport)
Thanks, I'll give it a try.

you probably need a BSR x5H cart which should give you about the same
output as the original and was a common replacement in the 70s when
those heavy crystal carts in old machines became incompatible when
stereo records appeared.

. But do try what martin suggests.

have you tried posting on Paul stenning's uk vintage repair and
restoration site forum? what the guys there don't know about these
matters ain't worth knowing! ;-)
-B

Bennett Price wrote:

In series? Don't you mean parallel?


Only if you want to cancle out most of the signal. They are out of
phase.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Mon, 23 Jul 2007 20:55:34 GMT, Bennett Price
wrote:


have you tried posting on Paul stenning's uk vintage repair and
restoration site forum? what the guys there don't know about these
matters ain't worth knowing! ;-)

Super site and Paul is very helpful - I have contacted him in the past
about radios I had. I have all his CDs of service sheets too which
cover a good many models that the BVWS discs don't.