Icom ICB-1050 ...

trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

GI7B

2010-06-24 16:28:06 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

Often the repeater shift.

Gerry

Jim.GM4DHJ/ Mobile...

2010-06-24 17:07:07 UTC

Post by GI7B

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

Often the repeater shift.
Gerry

not in this case ......

G4KFK

2010-06-24 17:27:41 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

The positive supply to the PA transistor Q306 goes through a series
pass transistor, Q304. The high/low switch appears to do something
with the bias on that transistor.

There's an adjustment related to it. I think it's RV301, but this
diagram is a bit fuzzy. Actually, it's a lot fuzzy.

G4KFK

2010-06-24 17:30:28 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

The positive supply to the PA transistor Q306 goes through a series
pass transistor, Q304. The high/low switch appears to do something
with the bias on that transistor.
There's an adjustment related to it. I think it's RV301, but this
diagram is a bit fuzzy. Actually, it's a lot fuzzy.

I'll scan this later this evening and stick it on line for you.

G4KFK

2010-06-24 18:17:20 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

Loading Image...

GM4DHJ in the Shack ...

2010-06-24 19:08:20 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

http://www.g4kfk.co.uk/ICB1050_1.jpg
http://www.g4kfk.co.uk/ICB1050_2.jpg
http://www.g4kfk.co.uk/ICB1050_3.jpg
http://www.g4kfk.co.uk/ICB1050_4.jpg
http://www.g4kfk.co.uk/ICB1050_5.jpg
http://www.g4kfk.co.uk/ICB1050_6.jpg
http://www.g4kfk.co.uk/ICB1050_7.jpg
http://www.g4kfk.co.uk/ICB1050_8.jpg

very nice...thanks .....

GM4DHJ in the Shack ...

2010-06-24 19:15:58 UTC

Post by GM4DHJ in the Shack ...
very nice...thanks .....

this one was modified by G4IWS lots of info on the conversion with ... but I
would have expected 100Kc/s repeater shift on the hi/low switch...

Steve Terry

2010-06-24 19:33:07 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

That brings back some memories

The JWR version has a 7mm 455khz IFT on pin 3 of the MC3357
giving much better IF gain
There was an off the shelf toko coil that would do the job

Also it's a good idea to fit the noise squelch the JWR version
uses, the board is etched for it just fit the components.
God knows why the Icom version has a useless botched
carrier squelch?
Of course you'll need a JWR cct diagram to find the differences,
unfortunately i lost mine years ago.

Steve Terry

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Nick B.

2010-06-25 09:20:44 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

That brings back some memories
The JWR version has a 7mm 455khz IFT on pin 3 of the MC3357
giving much better IF gain
There was an off the shelf toko coil that would do the job

John Woolfe Racing from Bedford, IIRC.

The MC3357 was well-known for getting hammered by strong signals, needed
a decent 10.7 filter in front of it.

Post by Steve Terry
Also it's a good idea to fit the noise squelch the JWR version
uses, the board is etched for it just fit the components.
God knows why the Icom version has a useless botched
carrier squelch?
Of course you'll need a JWR cct diagram to find the differences,
unfortunately i lost mine years ago.

I did an EPROM conversion on one of these just for the hell of it...

http://sites.google.com/site/nickb3332/10fmcircuits

--
Nick B.

Ian Jackson

2010-06-25 10:26:46 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

That brings back some memories
The JWR version has a 7mm 455khz IFT on pin 3 of the MC3357
giving much better IF gain
There was an off the shelf toko coil that would do the job

John Woolfe Racing from Bedford, IIRC.
The MC3357 was well-known for getting hammered by strong signals,
needed a decent 10.7 filter in front of it.

I did an EPROM conversion on one of these just for the hell of it...
http://sites.google.com/site/nickb3332/10fmcircuits

That's a useful site.

In the 1980s, I modified a few CB sets with the Cybernet chassis, as per
the Bury Amateur Radio Society information, using both an add-on
home-made boards and the Spectrum board. Great fun!

But be aware that with these - and also with the other mods for the
non-Cybernet sets, there is a good chance that there will also be RF
outputs on unintended frequencies. Some of these could be at a level
which might cause concern, and should be dealt with. You really do need
to check the purity of the TX output, preferably using a spectrum
analyser, between at least 25 to 35MHz.

--
Ian

Steve Terry

2010-06-25 21:59:34 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

That brings back some memories
The JWR version has a 7mm 455khz IFT on pin 3 of the MC3357
giving much better IF gain
There was an off the shelf toko coil that would do the job

John Woolfe Racing from Bedford, IIRC.
The MC3357 was well-known for getting hammered by strong signals,
needed a decent 10.7 filter in front of it.

Yes easy enough to fit a two pole Xtal filter (or two) replacing CF101

I did an EPROM conversion on one of these just for the hell of it...
http://sites.google.com/site/nickb3332/10fmcircuits
Nick B.

Nice, i used a pair of CD4008 in series on a piece of veroboard
with diodes on the second counter chain to make the difference
required, the advantage apart from being dead simple, is by simply
switching chains of diodes you can add a repeater shift and or
an extra band of 40 channel below 29.31 - 29.69, etc.

Steve Terry

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Steve Terry

2010-06-25 22:04:09 UTC

Post by G4KFK
I'll scan this later this evening and stick it on line for you.

That brings back some memories
The JWR version has a 7mm 455khz IFT on pin 3 of the MC3357
giving much better IF gain
There was an off the shelf toko coil that would do the job

John Woolfe Racing from Bedford, IIRC.

Has anyone the CCT diagram for a JWR M2 version?
It'd be well worth while comparing the differences.
Both use the same PCB.

The ICB1050 version must have saved as much as 10 pence
in production costs and resulted in a far inferior version.

Steve Terry

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Brian Reay

2010-06-24 17:35:14 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

The positive supply to the PA transistor Q306 goes through a series
pass transistor, Q304. The high/low switch appears to do something
with the bias on that transistor.
There's an adjustment related to it. I think it's RV301, but this
diagram is a bit fuzzy. Actually, it's a lot fuzzy.

It will probably be the hi/lo power switch.

As I recall, the 27/81 spec. required that CB radios could be switched from
4W to 400 (or 500) mW output.
The switch was to be used if the antenna was over a certain height.

Ask someone who was actually active a lot on CB, eg Gareth.

--
73
Brian G8OSN/W8OSN
www.g8osn.net

G4KFK

2010-06-24 17:45:45 UTC

Post by Brian Reay

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

The positive supply to the PA transistor Q306 goes through a series
pass transistor, Q304. The high/low switch appears to do something
with the bias on that transistor.
There's an adjustment related to it. I think it's RV301, but this
diagram is a bit fuzzy. Actually, it's a lot fuzzy.

It will probably be the hi/lo power switch.
As I recall, the 27/81 spec. required that CB radios could be switched from
4W to 400 (or 500) mW output.
The switch was to be used if the antenna was over a certain height.

IIRC, it was 10dB....

Post by Brian Reay
Ask someone who was actually active a lot on CB, eg Gareth.

.... or 1.1512925465 Nepers.

Brian Reay

2010-06-24 18:05:36 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low power
switch supposed to do? ........

The positive supply to the PA transistor Q306 goes through a series
pass transistor, Q304. The high/low switch appears to do something
with the bias on that transistor.
There's an adjustment related to it. I think it's RV301, but this
diagram is a bit fuzzy. Actually, it's a lot fuzzy.

It will probably be the hi/lo power switch.
As I recall, the 27/81 spec. required that CB radios could be switched from
4W to 400 (or 500) mW output.
The switch was to be used if the antenna was over a certain height.

IIRC, it was 10dB....

Don't mention dB, certain CBers struggle to understand the concept.

--
73
Brian G8OSN/W8OSN
www.g8osn.net

GM4DHJ in the Shack ...

2010-06-24 19:06:56 UTC

Post by Brian Reay
Ask someone who was actually active a lot on CB, eg Gareth.
--
73
Brian G8OSN/M3OSN
www.m3osn.net

nice put down .......

Paul Starship

2010-06-25 19:12:18 UTC

On Thu, 24 Jun 2010 18:35:14 +0100, "Brian Reay"

Post by Brian Reay
Ask someone who was actually active a lot on CB, eg Gareth.

what about your AMSTRAD 901 ?

Steve Terry

2010-06-24 19:19:27 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Switch to half a watt. On most of mine if not used for repeater shift
with a pair of CD4008, it's used to switch 5kHz steps after soldering
in the extra /2 divider in the xtal ref chain giving a 5kHz ref instead of
10kHz

Steve Terry

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g4xou

2010-06-26 12:38:09 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

Jim.GM4DHJ/ Mobile...

2010-06-26 15:59:12 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jim why not convert it back to cb and resell it ron g4xou

that is a good idea .......

Jim.GM4DHJ/ Mobile...

2010-06-26 15:59:12 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jim why not convert it back to cb and resell it ron g4xou

that is a good idea .......

Jim.GM4DHJ/ Mobile...

2010-06-26 17:32:21 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

Steve Terry

2010-06-27 02:02:12 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital

Steve Terry

--
Welcome Sign-up Bonus of £1 when you signup free at:
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Jim.GM4DHJ/ Mobile...

2010-06-27 08:34:06 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

Ian Jackson

2010-06-27 10:45:12 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.

--
Ian

Jim.GM4DHJ/ Mobile...

2010-06-27 11:17:37 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.
Ian

it is tainted then ......

Gareth Evans G4SDW

2010-06-27 11:24:35 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.

it is tainted then ......

As is much of the money around today. It taint yours and it taint mine.

Jim.GM4DHJ/ Mobile...

2010-06-27 11:27:57 UTC

Post by Gareth Evans G4SDW

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.

it is tainted then ......

As is much of the money around today. It taint yours and it taint mine.

first £15 and it taint mine any more ....

Gerald

2010-06-27 11:50:37 UTC

Post by Gareth Evans G4SDW
As is much of the money around today. It taint yours and it taint mine.

Just how long is it since you had a job?

Custos Custodum

2010-06-27 20:14:47 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the

high

Post by GM4DHJ in the Shack ...
low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.
Ian

it is tainted then ......

<http://www.urbandictionary.com/define.php?term=taint#>

GM4DHJ in the Shack ...

2010-06-27 20:26:29 UTC

Post by Custos Custodum

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the

high

Post by GM4DHJ in the Shack ...
low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.
Ian

it is tainted then ......

<http://www.urbandictionary.com/define.php?term=taint#>

well you learn something new every day ... some useless ........

Steve Terry

2010-06-28 00:36:22 UTC

Post by GM4DHJ in the Shack ...
trying out the Icom ICB-1050 i got at Newbury.....what is the high low
power switch supposed to do? ........

Jom why not convert it back to cb and resell it ron g4xou

or perhaps...land fill.....

But it's not digital
Steve Terry

I am thinking that it is .........

The synthesiser bit is.
Ian

Put a VFO in then

Steve Terry

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Jim Stewart

2010-06-28 06:57:07 UTC

Post by Jim.GM4DHJ/ Mobile...
I am thinking that it is .........

The synthesiser bit is.
Ian

Put a VFO in then
Steve Terry

don't be silly .....

Steve Terry

2010-06-28 17:19:35 UTC

Post by Jim Stewart

Post by Jim.GM4DHJ/ Mobile...
I am thinking that it is .........

The synthesiser bit is.
Ian

Put a VFO in then
Steve Terry

don't be silly .....

I'm very sorry, what was i thinking?

Steve Terry

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GM4DHJ in the Shack ...

2010-07-01 13:01:12 UTC

Post by Jim Stewart