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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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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:
?
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, 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:
?
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. :-)
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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:
?
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
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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:
?
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,
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Mike,
L7 is a T37-6 toroid. Joel KB6QVI
On Thu, Nov 24, 2016 at 9:42 AM, Mike Haynes mike.haynes08@... [BITX20] <BITX20@...> wrote:
?
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,
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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:
?
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
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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. ? ?
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You'll figure it out. Don't give in!
73 Ken
On Thu, Nov 24, 2016 at 8:27 PM, Mike Haynes mike.haynes08@... [BITX20] <BITX20@...> wrote:
?
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. ? ?
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mike, just? clean up the pads and solder a regular pnp in its place.
- f
On 25-Nov-2016 7:03 am, "Mike Haynes mike.haynes08@... [BITX20]" < BITX20@...> wrote:
?
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. ? ?
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Used a 2n3906 for Q13.
73 Ken
On Thu, Nov 24, 2016 at 8:27 PM, Mike Haynes mike.haynes08@... [BITX20] <BITX20@...> wrote:
?
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. ? ?
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Careful. I think you need a PNP so that's a 2N3906. 2N3904 are NPN. Check the schematic, I don't have access to it.
73 Ken
On Fri, Nov 25, 2016 at 8:33 AM, Mike Haynes mike.haynes08@... [BITX20] <BITX20@...> wrote:
?
I actually have a few 2N3904s in stock. Tonight is "pizza and Netflix" night though. So I'll put it in tomorrow and see what happens. :-)
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Q13 (BC849) is NPN. So I should be in good shape. :-) [image: Inline image 1] On Fri, Nov 25, 2016 at 7:43 AM, Ken Chase chase8043@... [BITX20] < BITX20@...> wrote:
Careful. I think you need a PNP so that's a 2N3906. 2N3904 are NPN. Check
the schematic, I don't have access to it.
73 Ken
On Fri, Nov 25, 2016 at 8:33 AM, Mike Haynes mike.haynes08@...
[BITX20] <BITX20@...> wrote:
I actually have a few 2N3904s in stock. Tonight is "pizza and Netflix"
night though. So I'll put it in tomorrow and see what happens. :-)
On Fri, Nov 25, 2016 at 5:16 AM, Mike Haynes <mike.haynes08@...>
wrote:
Good to know. Thanks Ken!
On Fri, Nov 25, 2016 at 5:09 AM, Ken Chase chase8043@... [BITX20]
<BITX20@...> wrote:
2N3904 and 2N3906 are very common transistors to use. Always keep
plenty on hand.
73 Ken
On Fri, Nov 25, 2016 at 6:03 AM, Mike Haynes mike.haynes08@...
[BITX20] <BITX20@...> wrote:
Thanks. I ordered 5 each of both types (I always buy extra). :-)
On Thu, Nov 24, 2016 at 8:13 PM, Ken Chase chase8043@...
[BITX20] <BITX20@...> wrote:
Used a 2n3906 for Q13.
73 Ken
On Thu, Nov 24, 2016 at 8:27 PM, Mike Haynes mike.haynes08@...
[BITX20] <BITX20@...> wrote:
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:
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:
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:
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:
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:
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
--
Mike Haynes
--
Mike Haynes
--
Mike Haynes
--
Mike Haynes
--
Mike Haynes
--
Mike Haynes
--
Mike Haynes
--
Mike Haynes
-- Mike Haynes [Non-text portions of this message have been removed]
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riggerswa@...
I still not sure what happened I put it in a aluminum box and it must have shorted out and died :(?
What died?? Is receive ok or transmit ok?? Can you measure voltages?? Let's have a look. . . .? Joe
On Thu, Nov 24, 2016 at 8:27 AM, riggerswa@... [BITX20] <BITX20@...> wrote:
?
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?
|
Nope no nothing :( Im back at work now for 2 weeks i work away from home for 2 weeks then home for 1? When i get back i will have another look
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Joel Caulkins/N6ALT