Date   

Re: ubitxv6 mic not working fine #ubitxv6

Evan Hand
 

rpremo,
First, verify that the mic/PTT plug is inserted correctly.  There may not be all the way inserted into the jack.  The PTT is between the ring and the sleeve of the plug.

I would then check the wiring on the PTT switch of the mic.  You could do this with a vom or DMM checking the continuity (resistance) between the ring and the sleeve of the mic plug.  The resistance should be 0 when the PTT switch on the mic is pressed, and very high (infinite or open) when the switch is open.

I would also verify that the condition does not happen when the mic is not plugged in as if you were operating in CW mode.  This would eliminate an issue on the mainboard, except for the 3.5 mm jack.

If plugged in correctly, then my guess is the wiring of the mic is intermittent.

73
Evan
AC9TU


Re: ubitxv6 mic not working fine #ubitxv6

rpremo
 

I recently received the Bitx6 having issues with the Microphone when I plug it in the TX constantly repetitively engages and releases.  Reminds me of the sound of a Antenna tuner trying to set the relays.  I read that these microphones are not good I have another Baofeng microphone with the Kenwood connector I would refer not to alter it unless this seems like the only recourse here.


Re: #v5 no #tx audio #ssb #v5 #tx

Reed N
 

Oh, looks like I left out C60 in my drawing (between MIC and the 1.93V measurement), but I don't think that changes any of the results.


Reed


Re: Transverter for 6 meters on eBay

Jens / DH1AKY
 

Hi Lou,

the crystal heater is this one
https://www.ebay.de/itm/184269586987

So you can take any normal size crystal 116 MHz.

73s, Jens/DH1AKY


Re: #v5 no #tx audio #ssb #v5 #tx

Reed N
 

Attached is the voltage measurements I get when transmitting on my v6. I think this circuit is the same as on v5, but some label numbers might be different.




Reed


Re: #v5 no #tx audio #ssb #v5 #tx

 

Tim,

I am guessing that since you say you get 12V means that the mic element is not connected.
The voltage should drop a bit when the mic is connected on TX. If what I am saying is correct
then open and check the mic element soldering. If you get 12V there and connection is fine
then replace element.

Raj

At 08/06/2020, you wrote:
Thanks, Evan, I'm getting closer.

I did in fact verify that I have +12v (or so) into the mic element when PTT is held. I thought that bias was there all the time, but your explanation covers that. (I'm making these tests into a 50-ohm load so I shouldn't be hurting anything on the PA side, BTW).

Confirmed continuity from R60 to the mic element (the ground side, hopefully that's what it's supposed to be).

Knowing that I do have voltage to the mic, should I still run the tests you suggested? Regarding the test with the audio connector disconnected--where would I measure? On the connector itself on the main board, or on the mic element? (Or to the PTT line?)

There is one other possibility here that's worth mentioning, which is that maybe my test itself was faulty. I don't think this is it, but I'll throw it out there. I tested by transmitting on the ubitx while listening on my TS-590s with no antenna connected to the Kenwood (the antenna was connected to the ubitx instead). With the TX antenna so close, though, I thought it could be possible that the Kenwood is de-sensing even with no antenna connected. I tried turning the RF gain on the Kenwood way down, but that didn't change things at all. S meter registered a carrier but no audio came through. Since I tested transmitting ubitx CW the same way and the Kenwood didn't de-sense on that test, I don't think that's the issue here. But figured I'd mention it.

-Tim


Re: #v5 no #tx audio #ssb #v5 #tx

Tim Helming
 

Thanks, Evan, I'm getting closer.

I did in fact verify that I have +12v (or so) into the mic element when PTT is held. I thought that bias was there all the time, but your explanation covers that. (I'm making these tests into a 50-ohm load so I shouldn't be hurting anything on the PA side, BTW). 

Confirmed continuity from R60 to the mic element (the ground side, hopefully that's what it's supposed to be).

Knowing that I do have voltage to the mic, should I still run the tests you suggested? Regarding the test with the audio connector disconnected--where would I measure? On the connector itself on the main board, or on the mic element? (Or to the PTT line?)

There is one other possibility here that's worth mentioning, which is that maybe my test itself was faulty. I don't think this is it, but I'll throw it out there. I tested by transmitting on the ubitx while listening on my TS-590s with no antenna connected to the Kenwood (the antenna was connected to the ubitx instead). With the TX antenna so close, though, I thought it could be possible that the Kenwood is de-sensing even with no antenna connected. I tried turning the RF gain on the Kenwood way down, but that didn't change things at all. S meter registered a carrier but no audio came through. Since I tested transmitting ubitx CW the same way and the Kenwood didn't de-sense on that test, I don't think that's the issue here. But figured I'd mention it.

-Tim


Re: #v5 no #tx audio #ssb #v5 #tx

Evan Hand
 

Tim,
It comes from the TX voltage (only there when transmitting) through R66 (220 ohms) and R60 (4.7 K ohms) to the "audio" connector on the mainboard and then is wired to the tip connection of the 3.5 mm mic/ptt jack.

Again, it is only on when the rig is in transmit mode.

My first guess would be a wiring problem.  Verify that you do get the voltage at the audio connector and then the mic jack.  You could also check continuity from R60 to the mic element.  That could isolate if it is the wiring or the resistor.  Also, try the voltage test with the audio connector disconnected at the board connector to verify if there is a short somewhere.  With the 4.7 K resistor in series, a direct short would not release any magic smoke and could be shorting out the voltage.

The above tests are best done with a dummy load, or better yet, with the PA power removed (brown wire in the three-wire power connector).  That may be difficult with one of the AmateurRadioKits enclosures.

Good luck with your hunt!
73
Evan
AC9TU


Re: #v5 no #tx audio #ssb #v5 #tx

Tim Helming
 

Thanks gents

SSB receive is good. Seems to be very well on frequency, received audio is good, sensitivity seems pretty decent. I did the BFO alignment using the tool, and it came out about as expected.

But I think you've hit upon part (or all?) of the issue. I get no voltage at all to the mic. Zilch, nada, dead as a doornail. I did re-check the wiring, and there's nothing that I can see that looks amiss. I'll look at the diagrams again and see if I can figure out where that voltage is supposed to be coming from.

Tim


Re: #v5 no #tx audio #ssb #v5 #tx

Evan Hand
 

Tim,
First off is the answer to Reed's question.  That will tell us if the SSB filter and the rest of the rig is aligned, as it is common for both transmit and receive. 

Another test would be to verify that the electret element is getting the bias voltage to work.  You should have somewhere between 7 and 12 volts on the positive side of the mic element (usually the tip of the 3.5 mm Mic and PPT plug).

Last that I can think of would be to verify that you are getting audio at TP20 when transmitting and speaking a loud HEEELOOOOOOOW or whistle into the mic.

So first verify that the rig BFO is aligned with the SSB filter when receiving.  Then check that the electret element is getting a bias voltage.  The last would be to verify that the mic preamp is working on TP20.

Let us know the results.

73
Evan
AC9TU


Re: #v5 no #tx audio #ssb #v5 #tx

Reed N
 

Does RX of SSB come in well, too? Or just CW?


Reed


#v5 no #tx audio #ssb #v5 #tx

Tim Helming
 

I'm ironing out the kinks and my v5 is coming together. If I can knock this one out then I'll be ready to go out and do some operating!

My TX is good and strong on CW. Waveform seems nicely shaped (to my ear anyway, listening through my main station rig), it's bang on frequency, RX is working nicely.

But when I try to transmit on SSB, while the transmitter keys and my station rig seems to pick up the carrier, no sound comes over the mic. The TX/RX relay works fine--everything seems good, but it's as if the mic were muted or something. 

I had another mic element very similar to the one the rig shipped with. Thinking it might be a bad element, I swapped them. No difference.

I did have the mic mis-wired at first, though never with its polarity reversed or with a dead short anywhere there shouldn't have been. But is there any possibility that miswiring could have damaged the modulation circuit or something?

73,

Tim WT1IM


Re: Transverter for 6 meters on eBay

kx4om
 

I bought the 6m to 10m  board from transverters-store on eBay for about $30 2 years ago to go with my HTX-100. He's selling the board plus the attenuator board for about that price now. At the time he was not selling a full unit with case.

Ted, KX4OM


Re: BitX 20 Build: Nylon washer or toroid #bitx20

Mick
 

I just recently ordered some toroids, they were reasonably priced and International delivery was “quick” took about 7 days to get to Sarnia Canada. Under normal conditions this is good delivery time from US to Canada.
They also have a nice turn calculator on line.
--
 

73
Mick VA3EPM 


Re: BitX 20 Build: Nylon washer or toroid #bitx20

ajparent1/kb1gmx <kb1gmx@...>
 

Pete and I go back some and I've shared a lot of knowledge and tricks with him.
Like building radios using shielded compartments and 3D construction using the
base and walls of said compartment for space efficiency.
I enjoy seeing what he does.

Allison
---------------------------------
No direct email, it goes to bit bucket due address harvesting in groups.IO


Re: BitX 20 Build: Nylon washer or toroid #bitx20

Dean Souleles
 

The correct URL is kitsandparts.com.  Easy to work with -good inventory of many parts for homebrewers.

https://kitsandparts.com/


73,
Dean
KK4DAS


Re: BitX 20 Build: Nylon washer or toroid #bitx20

Jim Strohm
 

>here are affordable toroid sources in the states, and from just dash 2, 6, 43 and maybe 61 you can make lots of inductors and transformers. See if w8diz partsandkits.com is still in
>business.

>Curt wb8yyy

It appears that the partsandkits website has been hijacked.

That's why I'm maintaining ownership of all my strohmforcongress websites for the rest of my life (about $300 a year).  If you're curious, look in the internet wayback machine for around November 2006.

I won't run again, but I may put the site up again as a blog, given today's interesting political and social climate in the states.  If I do, I'll post to QRZ.com, but probably not mention it here.  We're too global to talk about American political churn.

73
Jim N6OTQ


Re: BitX 20 Build: Nylon washer or toroid #bitx20

 

Drool, a beauty Pete! Great work! Brilliant!

Raj


At 07/06/2020, you wrote:
Hi Aaron,

I built the Bitx20 shortly after it was unveiled to the world and as it is now, it was then -- a solid design. The see how robust a design it was I used transistor sockets on all of the lower level stages and I cycled various transistors into the sockets --including a bag of obsolete 2N706 early on RF transistors. Even they worked except for one stage --the BFO where you had to cherry pick one that would consistently oscillate. Others that were tried include the 2N2222 and even a grab bag of no name NPN transistors. So that says much about a design that can take generic transistors and still work

There were several changes I made including not using the Teflon washers and I even shared the winding data for FT-37-43 cores. Several other changes included moving the IF to 9 MHz and adding the EI9GQ VFO stabilizer to keep the frequency locked. So homebrewing a Bitx 20 is indeed a viable approach. My call at that time was W6JFR. A special note --the main board is NOT perf board but instead a piece of single sided copper PC Board that was hand drilled using a perf board overlay. The continuous copper ground plane makes this work!

73's
Pete N6QW

approach[] [] []

[]


Re: BitX 20 Build: Nylon washer or toroid #bitx20

Jack, W8TEE
 

For those who may not know the N6QW call, it's Pete Juliano, and avid builder and co-host of the Solder and Smoke podcast, with a skill set that I'd give my left #%$ to have. If you want to see some neat stuff, check out his QRZ page. Oh...while you're there, check out more homebrew stuff by David Richards, AA7EE...it is an art form.

Jack, W8TEE

On Sunday, June 7, 2020, 10:08:16 AM EDT, N6QWHAM@... <n6qwham@...> wrote:


Hi Aaron,

I built the Bitx20 shortly after it was unveiled to the world and as it is now, it was then -- a solid design. The see how robust a design it was I used transistor sockets on all of the lower level stages and I cycled various transistors into the sockets --including a bag of obsolete 2N706 early on RF transistors. Even they worked except for one stage --the BFO where you had to cherry pick one that would consistently oscillate. Others that were tried include the 2N2222 and even a grab bag of no name NPN transistors. So that says much about a design that can take generic transistors and still work

There were several changes I made including not using the Teflon washers and I even shared the winding data for FT-37-43 cores. Several other changes included moving the IF to 9 MHz and adding the EI9GQ VFO stabilizer to keep the frequency locked. So homebrewing a Bitx 20 is indeed a viable approach. My call at that time was W6JFR. A special note --the main board is NOT perf board but instead a piece of single sided copper PC Board that was hand drilled using a perf board overlay. The continuous copper ground plane makes this work!

73's
Pete N6QW

approach



--
Jack, W8TEE


Re: BitX 20 Build: Nylon washer or toroid #bitx20

N6QWHAM@...
 

Hi Aaron,

I built the Bitx20 shortly after it was unveiled to the world and as it is now, it was then -- a solid design. The see how robust a design it was I used transistor sockets on all of the lower level stages and I cycled various transistors into the sockets --including a bag of obsolete 2N706 early on RF transistors. Even they worked except for one stage --the BFO where you had to cherry pick one that would consistently oscillate. Others that were tried include the 2N2222 and even a grab bag of no name NPN transistors. So that says much about a design that can take generic transistors and still work

There were several changes I made including not using the Teflon washers and I even shared the winding data for FT-37-43 cores. Several other changes included moving the IF to 9 MHz and adding the EI9GQ VFO stabilizer to keep the frequency locked. So homebrewing a Bitx 20 is indeed a viable approach. My call at that time was W6JFR. A special note --the main board is NOT perf board but instead a piece of single sided copper PC Board that was hand drilled using a perf board overlay. The continuous copper ground plane makes this work!

73's
Pete N6QW

approach