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Well, I made sure again that the transformers were not shorted. I was getting a high voltage on the base of Q13 (Pre amp BC849) and suspected it was bad. This is because the radio was working great at first before the power dropped. Then I discovered after the fact that the power supply I was using was not "well regulated" as I had thought (bought it used from a flea market), and it had been pushing about 18 volts. Oops. So I strongly suspected that I may have blown Q13 (Q14 & Q15 tested good out of circuit). So I bit the bullet and tried removing Q13. That did not go well. So now with that transistor in pieces, I really do need to replace Q13. I won't know if I was right until I get the replacement. If not, I am again stumped. I know I could spend another $45 to get a new board, but I don't want to give up on this one yet. ? ?

On Thu, Nov 24, 2016 at 12:02 PM, Mike Haynes <mike.haynes08@...> wrote:

Thanks Joel!

On Thu, Nov 24, 2016 at 11:56 AM, Mike Haynes <mike.haynes08@...> wrote:

Ashhar,

Yes, that is the one I'm talking about. I'll rewind as you instructed, and I'll double check the transformers for shorts as well.

On Thu, Nov 24, 2016 at 11:46 AM, Ashhar Farhan farhanbox@... [BITX20] <BITX20@...> wrote:

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Mike,

Are you talking about the PA filter inductor? pull it out and wind your own with 17 turns. If, you can retrieve it, then take a turn out ?and put it back as a 16 turn inductor, the value is not critical at all

- f

On Thu, Nov 24, 2016 at 11:12 PM, Mike Haynes mike.haynes08@... [BITX20] <BITX20@...> wrote:

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Hello Ashhar,

Thanks for the feed back. I don't have an oscilloscope unfortunately, but upon closer inspection, I noticed that the toroid for L7 (1.1 uH) is actually broken. A small sliver of it remains glued to the board, with the rest being supported only by the wire. I would imagine that would make a considerable change in the inductance value at least? If so, can you tell me what type of toroid is used so I can replace it?

Thanks,

On Thu, Nov 24, 2016 at 10:13 AM, Ashhar Farhan farhanbox@... [BITX20] <BITX20@...> wrote:

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Mike,

distortion is not cured by replacing the IRF510s. The low output is certainly due to the transformer windings being shorted. Pry them apart with a toothpick. Do you have an oscilloscope that you can shoot at it?

The fact that the receiver is working indicates that everything upto the band pass filters is working. Now, you have just three stages of the transmitter chain to debug. Can't be that tough...

- f

On Thu, Nov 24, 2016 at 9:04 PM, Mike Haynes mike.haynes08@... [BITX20] <BITX20@...> wrote:

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Good luck with the new one! I haven't given up on mine just yet. Receive is okay, but transmit is low power and distorted. I've got replacement IRF510s on the way (I ordered 5), and I'll see if that fixes it. If not, I might order a new one as well. :-)

On Thu, Nov 24, 2016 at 7:27 AM, riggerswa@... [BITX20] <BITX20@...> wrote:

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New one on the way. Note to self dont kill this one :)

I still not sure what happened i put it in a aliminium box and it must have

Shorted out and died :(?

So bigger box this time?

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Mike Haynes

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Mike Haynes

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Mike Haynes

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Mike Haynes

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Mike Haynes