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 Frog 40m Kit - R19 Conundrum? 
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Location: Stewkley, Bucks
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Post Frog 40m Kit - R19 Conundrum?
Hi all,

Just using one of the Ebay Frog kits as a basis for a 40m transceiver. They are cheap and cheerful. I had to chase them initially as they sent it without the Xtals.

Now everything is there it was fairly easy to put together. Everything is kind of working with about 1W out, but the double sided circuit board is a little bit difficult to decipher and indicates an R19 to be inserted, which is not on the circuit diagram or component list. Come to conclusion that the circuit diagram and kit board don't fully coincide!.

Any one else had this problem and found out what R19 should do and whether it os required?

Thanks,

Phil G4FVZ


Tue Sep 22, 2015 9:59 am
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 Frog 40m Kit - R19 Conundrum? 
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Joined: Sun Feb 23, 2014 7:09 pm
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Location: Blackpool, IO83LT
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Post Re: Frog 40m Kit - R19 Conundrum?
Hi Phil

I found this link which suggests that R19 is just a jumper

https://www.youtube.com/all_comments?v=aORGowhOJgI

Cheers

Dave
M6XMA

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Dave
M6XMA


Tue Sep 22, 2015 5:57 pm
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 Frog 40m Kit - R19 Conundrum? 
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Location: Stewkley, Bucks
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Post Re: Frog 40m Kit - R19 Conundrum?
Hi Dave,

Thanks for the reply and the web link.

This could be useful, but I think they may have recently changed the board again so the solution may not be the same.

Backtracking on the PCB, I have got a jumper may not be the best idea, but I'll experiment. I am getting about a watt out so I am pretty sure the PA stage is working OK.

If you or anybody else finds anything else out or has other info then please let me know!

Thanks once again,

Phil G4FVZ


Wed Sep 23, 2015 9:17 am
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 Frog 40m Kit - R19 Conundrum? 
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Post Re: Frog 40m Transceiver Kit - R19 Conundrum - Update
Don't know if anyone else has struggled with getting this working.

I had a problem with the PCB not matching the circuit diagram or the component list. C10 and R19 are poorly defined.

I also had a problem with a faulty diode and finally the kit is working well now.

It’s been a frustrating time, as I checked every component before I loaded it onto the PCB but must have missed the diode. You need to be really careful - the components are really poor quality.

I experimented with C10 and have decided on a value of 0.1uF.

I still have an issue of R19 to resolve which as far as I can tell is all related to the RX/TX switching. A 1K ohm resistor may be the fix to this.

The TX power is just under a watt.

This kit is more fidly than most, the component quality cannot be relied upon (I had to replace the pot as it was scratchy) , and the kit is full of extra components but sometimes misses them (it had a XTAL missing which I had to chase the kit supplier for).

Overall I think the design is good, with a quality PCB let down by cheap components - however I only paid about £8 on eBay so I guess you get what you pay for.

Anyway, got there in the end!

Phil
G4FVZ


Tue Oct 06, 2015 7:01 am
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