Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

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Default Battery testing

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.

It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?

--jsw


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On Sat, 19 Mar 2016 09:33:25 -0400
"Jim Wilkins" wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.


I've thought about getting one of those. I was thinking of using it as
a test load for my arc welder. The latter is infinitely adjustable but
the adjuster is pretty crude. I wanted to try measuring the open
circuit voltage and then try correlating that to a more accurate
welding output current. The reviews on that HF load were quite the
mixed bag and it cost just enough that I haven't done it...

It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?


For a smaller load that may be more repeatable you might try some glow
plugs. The usually draw around 5 to 10 amps. Some of the generics
aren't all that expensive.

--
Leon Fisk
Grand Rapids MI/Zone 5b
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Default Battery testing

These cheap testers are sold under many brand names.

I looked into them on amazon and the more knowledgeable reviews all
say that they are crap, made as cheaply as possible just to sell them.

i
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On Sat, 19 Mar 2016 10:15:07 -0400, Leon Fisk
wrote:

On Sat, 19 Mar 2016 09:33:25 -0400
"Jim Wilkins" wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.


I've thought about getting one of those. I was thinking of using it as
a test load for my arc welder. The latter is infinitely adjustable but
the adjuster is pretty crude. I wanted to try measuring the open
circuit voltage and then try correlating that to a more accurate
welding output current. The reviews on that HF load were quite the
mixed bag and it cost just enough that I haven't done it...

It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?


For a smaller load that may be more repeatable you might try some glow
plugs. The usually draw around 5 to 10 amps. Some of the generics
aren't all that expensive.

A bank of old sealed beam headlights works great. And you can use
them to draw a battery right down to dead if you want - unlike a glow
plug which you will most likely burn out.
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"Leon Fisk" wrote in message
...
On Sat, 19 Mar 2016 09:33:25 -0400
"Jim Wilkins" wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had
hoped
for, but it does what it's supposed to well enough.


I've thought about getting one of those. I was thinking of using it
as
a test load for my arc welder. The latter is infinitely adjustable
but
the adjuster is pretty crude. I wanted to try measuring the open
circuit voltage and then try correlating that to a more accurate
welding output current. The reviews on that HF load were quite the
mixed bag and it cost just enough that I haven't done it...

It seems to me that the current draw at the pass/fail voltage step
for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a
better
idea?


For a smaller load that may be more repeatable you might try some
glow
plugs. The usually draw around 5 to 10 amps. Some of the generics
aren't all that expensive.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email


I didn't mention my other hamfest acquisitions because they are
expensive new and hard to find used, for example:
http://www.newark.com/ohmite/rns1r0/...00w/dp/01F7634

I can set up a 12V resistor test load for up to about 50A, with some
gaps in the range of currents and a lot of exposed terminals and
stiff, springy wires. Someone could buy the HF carbon pile load new
for a lot less than that rheostat.

5 Ohms 150W is a useful size IF you get a good one.
http://www.amazon.com/uxcell%C2%AE-C.../dp/B0087ZCOMW
"I would give a zero star rating if possible."

A tubular variable power resistor very quickly becomes too hot to
adjust.

--jsw




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"Ignoramus12566" wrote in
message ...
These cheap testers are sold under many brand names.

I looked into them on amazon and the more knowledgeable reviews all
say that they are crap, made as cheaply as possible just to sell
them.

i


The construction of this blue HF one isn't that bad inside, nothing
cried out for repair or improvement. It has a (skywired) multiturn pot
in series to adjust the gain of the voltmeter plus the front zero
adjustment. The ammeter agrees with my analog 50A Weston ammeter and
my DC clamp-on as well as you might expect for an analog meter. Unlike
some similar ones they ran the separate voltage measuring wires inside
the heavy current cables, not tie-wrapped onto the outside.

--jsw


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wrote in message
...
On Sat, 19 Mar 2016 10:15:07 -0400, Leon Fisk
wrote:

On Sat, 19 Mar 2016 09:33:25 -0400
"Jim Wilkins" wrote:
....


A bank of old sealed beam headlights works great. And you can use
them to draw a battery right down to dead if you want - unlike a
glow
plug which you will most likely burn out.


I certainly -don't- want to drain them dead, so I use my 20 Amp solar
panel controller to cut off the load when the battery drops to 10.7V.

If you don't have solar a 12VDC to 120VAC inverter with a lamp or
heater load will work, but may cycle on and off. The solar
controller's cutoff and reconnect voltages are programmable.

I just measured a 4001 round high beam as 3.0A at 12.8V.

--jsw


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"Leon Fisk" wrote in message
...
On Sat, 19 Mar 2016 09:33:25 -0400
"Jim Wilkins" wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. ...


I've thought about getting one of those. I was thinking of using it
as
a test load for my arc welder. The latter is infinitely adjustable
but
the adjuster is pretty crude. I wanted to try measuring the open
circuit voltage and then try correlating that to a more accurate
welding output current. The reviews on that HF load were quite the
mixed bag and it cost just enough that I haven't done it...


The voltmeter on the HF 91129 tops out at 16V. It has a 15 second
timer circuit inside that may not take much more than that. I didn't
find another inexpensive carbon pile load, which is what I was
searching for, not specifically a 12V battery tester.

If the welder varies the primary - secondary coupling, series
inductance or shunt leakage you may not see a good correlation, since
a fairly high open-circuit voltage aids striking the arc and the
adjustment is to the source impedance.

At school I used a Lincoln Square Wave newer than mine, with a digital
current display. You can't read it while welding and you adjust
current by the puddle anyway, so the readout was no more helpful than
a knob pointer on a scale.

--jsw


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On Sat, 19 Mar 2016 15:22:42 -0400
"Jim Wilkins" wrote:

snip
The voltmeter on the HF 91129 tops out at 16V. It has a 15 second
timer circuit inside that may not take much more than that. I didn't
find another inexpensive carbon pile load, which is what I was
searching for, not specifically a 12V battery tester.


That could be problem without some modifications. Probably looking at
~60 vac. Of course I also have the AC to deal with too. Could be
completely unworkable. I know I talked myself out of getting one
because I didn't feel like it would work out well.

Looks like just using an amp meter and having a video camera on both
meters while putzing around would be the simplest way to go. If I ever
get around to it...

If the welder varies the primary - secondary coupling, series
inductance or shunt leakage you may not see a good correlation, since
a fairly high open-circuit voltage aids striking the arc and the
adjustment is to the source impedance.


I suspect that could be the way it goes too. The welder uses a movable
shunt I believe. Rather than over think the test set up I figured to
just hook up some meters and see how it acted.

At school I used a Lincoln Square Wave newer than mine, with a digital
current display. You can't read it while welding and you adjust
current by the puddle anyway, so the readout was no more helpful than
a knob pointer on a scale.


From what I've seen they let you pre-program the output current on a
digital display but that doesn't mean it is calibrated very well. And
that doesn't take into account your cable length and poor connections
along the way.

A lot of my welding is for little stuff here and there. Never get
enough run time to establish good settings. It would be nice to be able
to preset the machine to what worked good before or to say the low,
mid, or high end of what is recommended. Usually by the time I've
gotten a feel for how it is running, re-adjusted the output a tad, I'm
already done. On thick stuff it doesn't matter much but thinner
items...

--
Leon Fisk
Grand Rapids MI/Zone 5b
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I've used carbon piles to test very high current power supplies.
One needs to verify software. Set 800 amps at 5v and see what is
flowing. Set 1000 amps and see if the pile is smoking.

We actually smoked our pile once - man that was a fast race to
disconnect and start to float some co2 around it to cut off the air
and turn off the fire if any.

It was a bit more crunchy the next time we used it, inside it was toast.

We had 2000 Watts across it and it was rated at 1500. Was to be used
at max of 1000 by ourselves.

We never used them to ramp up/down since ours was a mechanical
'resistor'.

We had static voltages in hundreds of amps at fixed voltages variable I
fixed E.

We had IEEE 488 voltage programming with high current ability. The
boxes protected themselves by trimming the voltage back to limit the
current.


I would think you could use that but not by turning knobs in real time.
Set and switch & see. Set and switch & see. You might be watching
results of the 'machine' and not of the battery. Once you find
something specific, try to re-create or verify with another load.
Which then takes out the servo effect of the pile electronics and
heating... of electronics and pile. Hot pile, wrong results.

Martin

On 3/19/2016 8:33 AM, Jim Wilkins wrote:
Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.

It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?

--jsw




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Right - and you can see when the light blows out.

My father, years and years ago at White Sands, needed a load resistor
for a new design Radar system before dumping it out on the range.

He used 1000W bulbs - 1000 of them. Big radar. He had a special
room with lots of coolant and racks of bulbs. The Radar was certified
and went on line. Dad then had the bulbs salvaged by a local city
who used them in large storage areas. The purchasing man ordered
another set for the next month. They returned those and canceled
further orders.

The Radar Design then went to the Pacific Missile Range for use.


I also use the car head light as a low voltage bulb over the ways
are of my metal lathe and wood lathe. They are bright and worked.

Martin


On 3/19/2016 9:50 AM, wrote:
On Sat, 19 Mar 2016 10:15:07 -0400, Leon Fisk
wrote:

On Sat, 19 Mar 2016 09:33:25 -0400
"Jim Wilkins" wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.


I've thought about getting one of those. I was thinking of using it as
a test load for my arc welder. The latter is infinitely adjustable but
the adjuster is pretty crude. I wanted to try measuring the open
circuit voltage and then try correlating that to a more accurate
welding output current. The reviews on that HF load were quite the
mixed bag and it cost just enough that I haven't done it...

It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?


For a smaller load that may be more repeatable you might try some glow
plugs. The usually draw around 5 to 10 amps. Some of the generics
aren't all that expensive.

A bank of old sealed beam headlights works great. And you can use
them to draw a battery right down to dead if you want - unlike a glow
plug which you will most likely burn out.

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"Martin Eastburn" wrote in message
...
I've used carbon piles to test very high current power supplies.
One needs to verify software. Set 800 amps at 5v and see what is
flowing. Set 1000 amps and see if the pile is smoking.

We actually smoked our pile once - man that was a fast race to
disconnect and start to float some co2 around it to cut off the air
and turn off the fire if any.

It was a bit more crunchy the next time we used it, inside it was
toast.

We had 2000 Watts across it and it was rated at 1500. Was to be
used
at max of 1000 by ourselves.

We never used them to ramp up/down since ours was a mechanical
'resistor'.

We had static voltages in hundreds of amps at fixed voltages
variable I fixed E.

We had IEEE 488 voltage programming with high current ability. The
boxes protected themselves by trimming the voltage back to limit
the
current.


I would think you could use that but not by turning knobs in real
time.
Set and switch & see. Set and switch & see. You might be watching
results of the 'machine' and not of the battery. Once you find
something specific, try to re-create or verify with another load.
Which then takes out the servo effect of the pile electronics and
heating... of electronics and pile. Hot pile, wrong results.

Martin


I haven't seen a really big carbon pile load since the 70's, at a GM
plant. When I tested electric vehicle batteries we used an electronic
load that dumped its heat into a barrel of water. I'm very happy that
the testing program was quiet and uneventful and didn't produce any
hair-raising tales to pass on here.
--jsw


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Jim Wilkins wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.

It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?



https://archive.org/details/73-magazine-1976-11 look at the article 'The
Smoke Tester' (on page 159) for an adjustable solid state load.


Here is a link to just that one page article, on my Google Drive. It
is only 118 KB, VS 71 MB for the entire magazine.

https://drive.google.com/file/d/0B6A44wcq1oA4dUYza2Z6OXR0Nzg/view?usp=sharing
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On Wed, 23 Mar 2016 17:24:11 -0400, "Michael A. Terrell"
wrote:


Jim Wilkins wrote:

Yesterday I bought the HF 500A carbon pile battery tester 91129. The
instructions are aimed at a one time Go/NoGo garage test of customer
batteries, for 15 seconds at 1/2 of the CCA rating.
http://www.harborfreight.com/500-amp...ter-91129.html
The adjustment is unstable below 30A and drifts upward as the carbon
heats up. It isn't the good 5A or 10A discharge test load I had hoped
for, but it does what it's supposed to well enough.


Some of the other distributors for that model say "50-500A", but HF
doesn't. Any reason you didn't go with the 100A model, if you wanted
to test smaller currents, Jim?


It seems to me that the current draw at the pass/fail voltage step for
the ambient temperature would be a more sensitive indication of
battery condition -if- you record it to compare to later. There is a
large change in current for a small change in voltage, and the
pass/fail voltage point should be the same for any starting battery
size or condition.

Has anyone else used a variable load tester this way, or have a better
idea?



https://archive.org/details/73-magazine-1976-11 look at the article 'The
Smoke Tester' (on page 159) for an adjustable solid state load.


That was a fun romp in the Seventies. Ampl'Anny, eh? g

I just brought home some Kenwood TK715 VHF FM radios from my sister's.
She wants me to sell them for her. Any idea what they're worth?
They're NOS NIB (1 cardboard box missing, but still in styrofoam box)
Straight 715, not N or other suffix. Vehicle mount 25W HAM.

--
Never trouble another for what you can do for yourself.
-- Thomas Jefferson
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On Fri, 25 Mar 2016 20:43:57 -0700, Larry Jaques
wrote:

I just brought home some Kenwood TK715 VHF FM radios from my sister's.
She wants me to sell them for her. Any idea what they're worth?
They're NOS NIB (1 cardboard box missing, but still in styrofoam box)
Straight 715, not N or other suffix. Vehicle mount 25W HAM.


Not..exactly....

http://www.radioinfoboard.com/viewtopic.php?t=4534

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&u act=8&ved=0ahUKEwi9n_GFpd7LAhVW22MKHTuIBJ4QFgg4MAQ &url=http%3A%2F%2Fwww.repeater-builder.com%2Fkenwood%2Fpdfs%2Ftk-715-svc-man.pdf&usg=AFQjCNFEG1UaZ8GrLTN5ThumztsO9fdjBA&sig 2=bYxE5cxtLsas_3FQw4nmow

Its a 200mhz TRUNKING radio. Commercial band...though articles do
indicate that they can be hacked...somewhat..kinda sorta...a bit.





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On Sat, 26 Mar 2016 04:55:26 -0700, Gunner Asch
wrote:

On Fri, 25 Mar 2016 20:43:57 -0700, Larry Jaques
wrote:

I just brought home some Kenwood TK715 VHF FM radios from my sister's.
She wants me to sell them for her. Any idea what they're worth?
They're NOS NIB (1 cardboard box missing, but still in styrofoam box)
Straight 715, not N or other suffix. Vehicle mount 25W HAM.


Not..exactly....


I should have said "HAM compatible", huh?


http://www.radioinfoboard.com/viewtopic.php?t=4534

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&u act=8&ved=0ahUKEwi9n_GFpd7LAhVW22MKHTuIBJ4QFgg4MAQ &url=http%3A%2F%2Fwww.repeater-builder.com%2Fkenwood%2Fpdfs%2Ftk-715-svc-man.pdf&usg=AFQjCNFEG1UaZ8GrLTN5ThumztsO9fdjBA&sig 2=bYxE5cxtLsas_3FQw4nmow

Its a 200mhz TRUNKING radio. Commercial band...though articles do
indicate that they can be hacked...somewhat..kinda sorta...a bit.


Any idea who'd buy them and how much they're worth?

--
Doctors prescribe medicine of which they know little,
to cure diseases of which they know less,
in human beings of which they know nothing.
--Francois-Marie Arouet Voltaire, about 250 years ago
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On Saturday, March 26, 2016 at 3:22:20 PM UTC-4, Larry Jaques wrote:
On Sat, 26 Mar 2016 04:55:26 -0700, Gunner Asch
wrote:

On Fri, 25 Mar 2016 20:43:57 -0700, Larry Jaques
wrote:

I just brought home some Kenwood TK715 VHF FM radios from my sister's.
She wants me to sell them for her. Any idea what they're worth?
They're NOS NIB (1 cardboard box missing, but still in styrofoam box)
Straight 715, not N or other suffix. Vehicle mount 25W HAM.


Not..exactly....


I should have said "HAM compatible", huh?


http://www.radioinfoboard.com/viewtopic.php?t=4534

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&u act=8&ved=0ahUKEwi9n_GFpd7LAhVW22MKHTuIBJ4QFgg4MAQ &url=http%3A%2F%2Fwww.repeater-builder.com%2Fkenwood%2Fpdfs%2Ftk-715-svc-man.pdf&usg=AFQjCNFEG1UaZ8GrLTN5ThumztsO9fdjBA&sig 2=bYxE5cxtLsas_3FQw4nmow

Its a 200mhz TRUNKING radio. Commercial band...though articles do
indicate that they can be hacked...somewhat..kinda sorta...a bit.


Any idea who'd buy them and how much they're worth?


Sure, I guess they'd sell in flea markets. Plenty of maturer folk would like them, maybe to flip on the pre-tuned weather in the morning. Its easier than thumbing through some phone in the bathroom.
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"Gunner Asch" wrote in message
...
On Fri, 25 Mar 2016 20:43:57 -0700, Larry Jaques
wrote:

I just brought home some Kenwood TK715 VHF FM radios from my
sister's.
She wants me to sell them for her. Any idea what they're worth?
They're NOS NIB (1 cardboard box missing, but still in styrofoam
box)
Straight 715, not N or other suffix. Vehicle mount 25W HAM.


Not..exactly....

http://www.radioinfoboard.com/viewtopic.php?t=4534

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&u act=8&ved=0ahUKEwi9n_GFpd7LAhVW22MKHTuIBJ4QFgg4MAQ &url=http%3A%2F%2Fwww.repeater-builder.com%2Fkenwood%2Fpdfs%2Ftk-715-svc-man.pdf&usg=AFQjCNFEG1UaZ8GrLTN5ThumztsO9fdjBA&sig 2=bYxE5cxtLsas_3FQw4nmow

Its a 200mhz TRUNKING radio. Commercial band...though articles do
indicate that they can be hacked...somewhat..kinda sorta...a bit.


200 MHz is within broadcast TV channel 11 (198-204MHz).

I know because I have to watch the shape of the channel on a spectrum
analyzer while rotating the antenna, to minimize reflections.
This shows multipath interference on channel 9 and a decent signal on
channel 12:
http://www.hdtvexpert.com/wp-content...e-Amp-1024.jpg

--jsw


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Default Battery testing


Jim Wilkins wrote:

"Gunner Asch" wrote in message
...
On Fri, 25 Mar 2016 20:43:57 -0700, Larry Jaques
wrote:

I just brought home some Kenwood TK715 VHF FM radios from my
sister's.
She wants me to sell them for her. Any idea what they're worth?
They're NOS NIB (1 cardboard box missing, but still in styrofoam
box)
Straight 715, not N or other suffix. Vehicle mount 25W HAM.


Not..exactly....

http://www.radioinfoboard.com/viewtopic.php?t=4534

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&u act=8&ved=0ahUKEwi9n_GFpd7LAhVW22MKHTuIBJ4QFgg4MAQ &url=http%3A%2F%2Fwww.repeater-builder.com%2Fkenwood%2Fpdfs%2Ftk-715-svc-man.pdf&usg=AFQjCNFEG1UaZ8GrLTN5ThumztsO9fdjBA&sig 2=bYxE5cxtLsas_3FQw4nmow

Its a 200mhz TRUNKING radio. Commercial band...though articles do
indicate that they can be hacked...somewhat..kinda sorta...a bit.


200 MHz is within broadcast TV channel 11 (198-204MHz).

I know because I have to watch the shape of the channel on a spectrum
analyzer while rotating the antenna, to minimize reflections.
This shows multipath interference on channel 9 and a decent signal on
channel 12:
http://www.hdtvexpert.com/wp-content...e-Amp-1024.jpg

--jsw



The manual says it is 177.2125 - 207.485 MHz, depending on the sub
band. It requires a Kenwood programming software and a KPG-4 Programming
interface. I only saw one sold listing for the radio on Ebay, and it
was under $50.

http://www.repeater-builder.com/kenw...15-svc-man.pdf
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