Commtron CB 40f TX "fart" issue

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The Collector
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Commtron CB 40f TX "fart" issue

Post by The Collector » 15 May 2019, 18:33

Bought a cute little Commtron 40f ukfm radio, a Ham Int. Relax mic' and a Marko mic' for £1.24 recently. I know this radio therefore could just be chucked in the bin, but I'd like to try and get her working 100%.

The Commtron seems to work great (have hardwired her, with an inline-fuse too) except, it "farts" on transmit, but just on channel 1. Sounds a bit like someone blowing a raspberry. It starts fast then slows down and stops after about 4 seconds. Could be what some called "motorboating"???
It did do it for a fraction of a second on channel 2 too but seemed okay after a minute's use.

I've gently twiddled the little red trimmer on the board (but my Tandy-bought 30 year old pot-twiddling sticks are a bit pants to be honest) to no avail.

Anyone know what component/s I need to be concentrating on and what size hammer to use please? ;)

It certainly wouldn't be worth sending this off for repair as the repair costs and postage would far outweight its worth.

There is a chance I may be able to do a Youtube vid', but I'm sure people in the know, know exactly what sort of noise I'm referring to.


Thanks in advance,
Dave.

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Buick Mackane
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Re: Commtron CB 40f TX "fart" issue

Post by Buick Mackane » 15 May 2019, 18:57

The Collector wrote:
15 May 2019, 18:33

The Commtron seems to work great except, it "farts" on transmit,
Dave.
That's because its utter sh1te dave :lol:

Sounds like the VCO Might not be locking properly
I Was asked to QSL Via the Bureau, But the FBI Said i'll be prosecuted if i phone them again, :shock:

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Re: Commtron CB 40f TX "fart" issue

Post by NightProwler » 15 May 2019, 19:15

Buick Mackane wrote:
15 May 2019, 18:57
The Collector wrote:
15 May 2019, 18:33

The Commtron seems to work great except, it "farts" on transmit,
Dave.
That's because its utter sh1te dave :lol:
:lol: :lol: :lol:
Shorter of breath and one day closer to death

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The Collector
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Re: Commtron CB 40f TX "fart" issue

Post by The Collector » 15 May 2019, 21:50

I've come to expect nothing less from Mr.Buick. I try and ask for help and all I get it this kind of thing.

Git!

;)


I know it's sh**e, but it's my 1p's worth of sh**e and I want to see if it'll work properly so it ends up as 2p's worth of sh**e, thank you very much :)

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Re: Commtron CB 40f TX "fart" issue

Post by astradyne » 16 May 2019, 07:30

The Collector wrote:
15 May 2019, 18:33
Bought a cute little Commtron 40f ukfm radio, a Ham Int. Relax mic' and a Marko mic' for £1.24 recently. I know this radio therefore could just be chucked in the bin, but I'd like to try and get her working 100%.

The Commtron seems to work great (have hardwired her, with an inline-fuse too) except, it "farts" on transmit, but just on channel 1. Sounds a bit like someone blowing a raspberry. It starts fast then slows down and stops after about 4 seconds. Could be what some called "motorboating"???
It did do it for a fraction of a second on channel 2 too but seemed okay after a minute's use.

I've gently twiddled the little red trimmer on the board (but my Tandy-bought 30 year old pot-twiddling sticks are a bit pants to be honest) to no avail.

Anyone know what component/s I need to be concentrating on and what size hammer to use please? ;)

It certainly wouldn't be worth sending this off for repair as the repair costs and postage would far outweight its worth.

There is a chance I may be able to do a Youtube vid', but I'm sure people in the know, know exactly what sort of noise I'm referring to.


Thanks in advance,
Dave.
Be careful Dave.

Farting on channel 1 can lead to full blown diarrhoea on channel 19! :lol:
Never, ever, ever....bloody anything ever!

Far too many radio's to list here. But I do own a legal one...

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Re: Commtron CB 40f TX "fart" issue

Post by The Collector » 16 May 2019, 11:59

Constructive criticism I can take, but just taking the pi$$ is about all I get on here. I'd get more helpful comments by posting my woes on bloody "mumsnet" than I would on here! :lol:

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Re: Commtron CB 40f TX "fart" issue

Post by Buick Mackane » 16 May 2019, 12:17

The Collector wrote:
16 May 2019, 11:59
Constructive criticism I can take, but just taking the pi$$ is about all I get on here. I'd get more helpful comments by posting my woes on bloody "mumsnet" than I would on here! :lol:
No Sh1t :lol:

I did mention earlier that it sounded like the VCO Was struggling to lock on the low channels
I Was asked to QSL Via the Bureau, But the FBI Said i'll be prosecuted if i phone them again, :shock:

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Re: Commtron CB 40f TX "fart" issue

Post by The Collector » 16 May 2019, 19:30

Well, I got my little cheap Draper miniture screwdriver set out and twiddled away. Adjusting the tiny red trimmer again did bugger all, so I just went through all the telephone box-shaped pots and twiddled those and if nothing happened, put them back to where they were originally. At one point I got rid of the farting but lost 90% of my incoming audio. A pot with a red-tinged slotted core in got adjusted and bought the audio back, so she now looks to be working :) I also turned the outgoing audio up as it was a tad quiet while I was at it.

I'm now offering my services as a fully-trained radio technician to all on TM1. There's no actual guarantee I'll fix anything, but I won't charge you much for trying. If it goes bang, it was probably knackered and about to blow up anyway! ;)

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