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I managed to kill my bitx40. It was working great until I decided to tune up the big rig. I can still receive. No power at all on transmit. I replace the 510 transistor. Sill no output. The current does jump up to over 1 amp when I switch to transmit.
Any idea what to look at next?
|
Bill - I believe I did the same thing to my BITX40 as, now when I flip the switch to transmit, it stays in the receive mode, but the frequency shifts slightly. No sure if the relay switches or if I blew the PA final. Receiver is fine, like your receive. I thought I may have left the radio in transmit mode when I switched off the volume control pot overnight ?(as I had planned to keep the radio powered on) but now believe that the issue may have resulted from using my TS-480 in transmit to locate my BITX40 frequency. Have been hoping to see Farahan's "troubleshooting the BITX40 transmitter" YouTube video, but I guess it still is "in production." If you receive any feedback on correcting your transmit side issues of the BITX40 could you please share this information with me? I ordered the IFR510 and 2n2219a from W8DIZ, but I hope to identify the issue before replacing the parts, if their replacement is even required. 73 ?and tks. W4USF - John - Lutz, FL.
Sent from my iPhone
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On Dec 31, 2016, at 07:07, Bill Kittilson bill@... [BITX20] < BITX20@...> wrote:
?
I managed to kill my bitx40. It was working great until I decided to tune up the big rig. I can still receive. No power at all on transmit. I replace the 510 transistor. Sill no output. The current does jump up to over 1 amp when I switch to transmit.
Any idea what to look at next?
|
Bill,
Check L6 and L7 and see if it is making contact with the solder on the board.
Check the relay K2, I seriously suspect that it could be faulty. Take the output from K2 pin 16 and ground to a (bnc) connector and check the TX out there with a power meter. If there is normal output then relay is suspect.. or not operating. When you
press PTT the relay should click, you should feel that with your finger. I have seen a lot of similar relays fail in my service
experience.
Cood luck and Happy new year!
Raj vu2zap
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At 31/12/2016, Bill Kittilson bill@... [BITX20] wrote:
I managed to kill my bitx40. It was working great until I decided to tune up the big rig. I can still receive. No power at all on transmit. I replace the 510 transistor. Sill no output. The current does jump up to over 1 amp when I switch to transmit.
Any idea what to look at next?
|
John,
Check if you have correct voltage at the TX and RX points. They come from
relay K1 - it could be faulty or not operating.
Good luck and Happy new year!
Raj vu2zap
At 31/12/2016, you wrote:
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Show quoted text
?
Bill - I believe I did the same thing to my BITX40 as, now when I flip
the switch to transmit, it stays in the receive mode, but the frequency
shifts slightly. No sure if the relay switches or if I blew the PA final.
Receiver is fine, like your receive. I thought I may have left the radio
in transmit mode when I switched off the volume control pot
overnight? (as I had planned to keep the radio powered on) but now
believe that the issue may have resulted from using my TS-480 in transmit
to locate my BITX40 frequency. Have been hoping to see Farahan's
"troubleshooting the BITX40 transmitter" YouTube video, but I
guess it still is "in production." If you receive any feedback
on correcting your transmit side issues of the BITX40 could you please
share this information with me? I ordered the IFR510 and 2n2219a from
W8DIZ, but I hope to identify the issue before replacing the parts, if
their replacement is even required. 73? and tks. W4USF - John -
Lutz, FL.
Sent from my iPhone
On Dec 31, 2016, at 07:07, Bill Kittilson
bill@... [BITX20]
<BITX20@...
> wrote:
?
I managed to kill my bitx40. It was working great until I decided to tune
up the big rig. I can still receive. No power at all on transmit. I
replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
Any idea what to look at next?
|
I can hear the bitx on a near by receiver. ?The coils look fine. The 510 gets hot on transmit. ?I hear the relay but it don't sound quite right. I order the replacement relays. I hope it's the simple. ?Thanks. I'll update you when i get the replacement. ?
Thanks.?
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Show quoted text
On Jan 1, 2017, at 1:56 AM, Raj vu2zap@... [BITX20] < BITX20@...> wrote:
?
Bill,
Check L6 and L7 and see if it is making contact with the solder on the board.
Check the relay K2, I seriously suspect that it could be faulty. Take the output from K2 pin 16 and ground to a (bnc) connector and check the TX out there with a power meter. If there is normal output then relay is suspect.. or not operating. When you
press PTT the relay should click, you should feel that with your finger. I have seen a lot of similar relays fail in my service
experience.
Cood luck and Happy new year!
Raj vu2zap
At 31/12/2016, Bill Kittilson bill@... [BITX20] wrote:
>
>
>I managed to kill my bitx40. It was working great until I decided to tune up the big rig. I can still receive. No power at all on transmit. I replace the 510 transistor. Sill no output. The current does jump up to over 1 amp when I switch to transmit.
>
>Any idea what to look at next?
|
disconnect the PA power line. Push the PTT and check if the transmit relay is switching. measure the connectivity with a VOM. copy?
- f
On Sun, Jan 1, 2017 at 8:04 PM, Bill Kittilson bill@... [BITX20] <BITX20@...> wrote:
?
I can hear the bitx on a near by receiver.? The coils look fine. The 510 gets hot on transmit.? I hear the relay but it don't sound quite right. I order the replacement relays. I hope it's the simple.? Thanks. I'll update you when i get the replacement. ?
Thanks.?
?
Bill,
Check L6 and L7 and see if it is making contact with the solder on the board.
Check the relay K2, I seriously suspect that it could be faulty. Take the output from K2 pin 16 and ground to a (bnc) connector and check the TX out there with a power meter. If there is normal output then relay is suspect.. or not operating. When you
press PTT the relay should click, you should feel that with your finger. I have seen a lot of similar relays fail in my service
experience.
Cood luck and Happy new year!
Raj vu2zap
At 31/12/2016, Bill Kittilson bill@... [BITX20] wrote:
>
>
>I managed to kill my bitx40. It was working great until I decided to tune up the big rig. I can still receive. No power at all on transmit. I replace the 510 transistor. Sill no output. The current does jump up to over 1 amp when I switch to transmit.
>
>Any idea what to look at next?
|
I have no conductivity between the outside pins and middle ones. when the button is pushed. When release I do have conductivity between the center pins and inner pins. I hear the relay clicking. ? Looks like the relay contacts went bad??
I order a replacement relay.?
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On Jan 1, 2017, at 12:33 PM, Ashhar Farhan farhanbox@... [BITX20] < BITX20@...> wrote:
?
disconnect the PA power line. Push the PTT and check if the transmit relay is switching. measure the connectivity with a VOM. copy?
- f
|
that's not how it is wired. refer to the circuit on? to see the pins, they are numbered like a 16 pin dip IC.
- f
On Sun, Jan 1, 2017 at 11:22 PM, Bill Kittilson bill@... [BITX20] <BITX20@...> wrote:
?
I have no conductivity between the outside pins and middle ones. when the button is pushed. When release I do have conductivity between the center pins and inner pins. I hear the relay clicking. ? Looks like the relay contacts went bad??
I order a replacement relay.?
?
disconnect the PA power line. Push the PTT and check if the transmit relay is switching. measure the connectivity with a VOM. copy?
- f
|
|
|
Sometimes, I use IC base for those relays...
'Repair & Reuse or Recycle E-Waste'
|
If the 510 gets hot, I'd check for shorts in the coils of the low pass filter or the antenna connector.?
If you are intending to replace the relay, you could pull it out and short the connectors for transmit. If the fault IS the relay, then you would get an output. If you still have low output, then chances are the fault is elsewhere?
73 Dave G4UFS
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On 1 Jan 2017, at 14:34, Bill Kittilson bill@... [BITX20] < BITX20@...> wrote:
?
I can hear the bitx on a near by receiver. ?The coils look fine. The 510 gets hot on transmit. ?I hear the relay but it don't sound quite right. I order the replacement relays. I hope it's the simple. ?Thanks. I'll update you when i get the replacement. ?
Thanks.?
?
Bill,
Check L6 and L7 and see if it is making contact with the solder on the board.
Check the relay K2, I seriously suspect that it could be faulty. Take the output from K2 pin 16 and ground to a (bnc) connector and check the TX out there with a power meter. If there is normal output then relay is suspect.. or not operating. When you
press PTT the relay should click, you should feel that with your finger. I have seen a lot of similar relays fail in my service
experience.
Cood luck and Happy new year!
Raj vu2zap
At 31/12/2016, Bill Kittilson bill@... [BITX20] wrote:
>
>
>I managed to kill my bitx40. It was working great until I decided to tune up the big rig. I can still receive. No power at all on transmit. I replace the 510 transistor. Sill no output. The current does jump up to over 1 amp when I switch to transmit.
>
>Any idea what to look at next?
|
Bill,
One question, when you switch to transmit does the current jump to 1A
when you speak into the mic or without speaking?
Raj
At 01/01/2017, you wrote:
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?
- At 31/12/2016, Bill Kittilson
bill@... [BITX20]
wrote:
- >
- >
- >I managed to kill my bitx40. It was working great until I decided
to tune up the big rig. I can still receive. No power at all on transmit.
I replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
|
toggle quoted message
Show quoted text
On Jan 1, 2017, at 10:22 PM, Raj vu2zap@... [BITX20] < BITX20@...> wrote:
?
Bill,
One question, when you switch to transmit does the current jump to 1A
when you speak into the mic or without speaking?
Raj
At 01/01/2017, you wrote:
?
- At 31/12/2016, Bill Kittilson
bill@... [BITX20]
wrote:
- >
- >
- >I managed to kill my bitx40. It was working great until I decided
to tune up the big rig. I can still receive. No power at all on transmit.
I replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
|
If the final bias adjust preset is untouched then the IRF may have
failed.
Check the voltage on the left side gate pin of IRF (facing you) it should
be a small value,
I don't have my boards with me here at the farm!
It could be the driver or predriver. Whichever is running hot when you
press the PTT!
At 02/01/2017, you wrote:
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?
Without speaking
On Jan 1, 2017, at 10:22 PM, Raj
vu2zap@... [BITX20]
<BITX20@...
> wrote:
?
Bill,
One question, when you switch to transmit does the current jump to 1A
when you speak into the mic or without speaking?
Raj
At 01/01/2017, you wrote:
?
- At 31/12/2016, Bill Kittilson
bill@... [BITX20]
wrote:
- >
- >
- >I managed to kill my bitx40. It was working great until I decided
to tune up the big rig. I can still receive. No power at all on transmit.
I replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
|
Bill,
While looking at the diagram again it occurred to me that if Q14 was
shorted, the power supply would get
2.2 + 10 Ohm load and that would draw almost 1 amp from a 12V power
supply.
Please check Q14 collector to emitter continuity with the power
off.
At 02/01/2017, you wrote:
toggle quoted message
Show quoted text
?
Without speaking
On Jan 1, 2017, at 10:22 PM, Raj
vu2zap@... [BITX20]
<BITX20@...
> wrote:
?
Bill,
One question, when you switch to transmit does the current jump to 1A
when you speak into the mic or without speaking?
Raj
At 01/01/2017, you wrote:
?
- At 31/12/2016, Bill Kittilson
bill@... [BITX20]
wrote:
- >
- >
- >I managed to kill my bitx40. It was working great until I decided
to tune up the big rig. I can still receive. No power at all on transmit.
I replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
|
I tested and getting 330 ohms. ?Receive current is 100ma no signal.
Transmit is anywhere from 180 ma to almost one amp depending where RV 1 is set to
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On Jan 2, 2017, at 6:00 AM, Raj vu2zap@... [BITX20] < BITX20@...> wrote:
?
Bill,
While looking at the diagram again it occurred to me that if Q14 was
shorted, the power supply would get
2.2 + 10 Ohm load and that would draw almost 1 amp from a 12V power
supply.
Please check Q14 collector to emitter continuity with the power
off.
At 02/01/2017, you wrote:
?
Without speaking
On Jan 1, 2017, at 10:22 PM, Raj
vu2zap@... [BITX20]
<BITX20@...
> wrote:
?
Bill,
One question, when you switch to transmit does the current jump to 1A
when you speak into the mic or without speaking?
Raj
At 01/01/2017, you wrote:
?
- At 31/12/2016, Bill Kittilson
bill@... [BITX20]
wrote:
- >
- >
- >I managed to kill my bitx40. It was working great until I decided
to tune up the big rig. I can still receive. No power at all on transmit.
I replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
|
Hi Bill,
What you observe means that the final stage is fine . Please set the
current back to the recommended
level and check the previous stages.
While in TX mode and not speaking in the mic - Check the Q13 and 14 base
to emitter voltage.
It should be around 0.7V +-0.1 - if 0 or >1V then replace
transistor.
Raj
t 02-01-2017, you wrote:
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?
I tested and getting 330 ohms.? Receive current is 100ma no
signal.
Transmit is anywhere from 180 ma to almost one amp depending where RV 1
is set to
On Jan 2, 2017, at 6:00 AM, Raj
vu2zap@... [BITX20]
<BITX20@...
> wrote:
?
Bill,
While looking at the diagram again it occurred to me that if Q14 was
shorted, the power supply would get
2.2 + 10 Ohm load and that would draw almost 1 amp from a 12V power
supply.
Please check Q14 collector to emitter continuity with the power
off.
At 02/01/2017, you wrote:
?
Without speaking
On Jan 1, 2017, at 10:22 PM, Raj
vu2zap@... [BITX20]
<BITX20@...
> wrote:
?
Bill,
One question, when you switch to transmit does the current jump to 1A
when you speak into the mic or without speaking?
Raj
At 01/01/2017, you wrote:
?
- At 31/12/2016, Bill Kittilson
bill@... [BITX20]
wrote:
- >
- >
- >I managed to kill my bitx40. It was working great until I decided
to tune up the big rig. I can still receive. No power at all on transmit.
I replace the 510 transistor. Sill no output. The current does jump up to
over 1 amp when I switch to transmit.
|
A friend had a similar problem. ?
The base & emitter voltages around Q13 were around 1 volt rather than 3.7v (base) and 3.1v (emitter). ?We fixed it by replacing Q13. ?If you're careful you can use a leaded transistor as the replacement.? Described at? | | | | | | A repair of a 'no power on transmit' fault suffered by a friend's Bitx40. | | | | Preview by Yahoo | | | ? ?
|
I get .9 volt in transmit on base and emitter. Collator is 12 volts I order replacements. ?Sounds like I have the same issue. ?
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On Jan 3, 2017, at 6:42 AM, parkerp@... [BITX20] < BITX20@...> wrote:
?
A friend had a similar problem. ?
The base & emitter voltages around Q13 were around 1 volt rather than 3.7v (base) and 3.1v (emitter). ?We fixed it by replacing Q13. ?If you're careful you can use a leaded transistor as the replacement.? Described at? | | | | | | A repair of a 'no power on transmit' fault suffered by a friend's Bitx40. | | | | Preview by Yahoo | | | ? ?
|
I order a replacement transistor. But it's going to take a couple weeks. ?I have a few different NPN transistor that have leads. ?What's a good replacement? 2N3904?
toggle quoted message
Show quoted text
On Jan 3, 2017, at 6:42 AM, parkerp@... [BITX20] < BITX20@...> wrote:
?
A friend had a similar problem. ?
The base & emitter voltages around Q13 were around 1 volt rather than 3.7v (base) and 3.1v (emitter). ?We fixed it by replacing Q13. ?If you're careful you can use a leaded transistor as the replacement.? Described at? | | | | | | A repair of a 'no power on transmit' fault suffered by a friend's Bitx40. | | | | Preview by Yahoo | | | ? ?
|
Raj vu2zap