Re: uBITX v6 Low Audio Update 11-23-24
Richard,
I have had 2 boards with dry solder on the diodes D1-D5 - three
legs each may need soldering.
Same or similar symptoms. While probing signal level i noticed
the sudden jump in volume when
I pressed a diodes leg. Re-soldering it cured the rigs.
Raj
On 24/11/2024 12:30 AM, Richard AG5M
via groups.io wrote:
toggle quoted message
Show quoted text
Tried again this morning, this time on the correct TP, TP21.
I have 53.6K on RX, 2.1 ohm on TX. So according to what you
(Evan) said, that's right. Everything is right so far, but I
have weak audio.
Time to get out the O-Scope? I do not have a schematic, does
anyone have one? I used it this morning to check into the
Noon-Time-Net with CW so other than weak audio it appears to be
working FB. BTW, is there a setting to reduce the sidetone
level? It's really loud!
I'm surprised that other than through this Forum, HFsignals
provides no support. Makes me a little hesitant to purchase a
radio from them. Given this experience.
73, Richard AG5M
On Friday, November 22, 2024 at 02:55:55 PM PST, Richard
AG5M via groups.io <ag5m@...> wrote:
Taking another run at this, I confirm I have Zero
volts RX at the gate of Q74, if the gate pin is the
one closest to D14. And I have 5 volts when in TX
mode. Given this information and what's noted below,
dos this tell anyone anything? Why I have virtually no
audio?
73, Richard AG5M
On Thursday, November 21, 2024 at 11:03:28 AM
PST, Richard AG5M via groups.io
<ag5m@...> wrote:
Evan and others who may be following.
The TP1 and TP2 I mentioned below was a typo,
they were TP20 and TP21. I did the same this
morning. With volume control fully clockwise.
Nice loud hum at Pin 3. Considerably lower hum
at TP21, and almost no hum at TP21. Turning
the volume control made difference.
This morning I checked the resistance
measurements you mentioned at TP20. With radio
on it measured 70 ohms RX, 2.36K TX. From what
you mentioned then I guess Q74 is faulty? I
did not make voltage measurement yet. Where
exactly is Q74? I don't see it.
73, Richard AG5M
On Tuesday, November 19, 2024 at
05:09:11 PM PST, Evan Hand via groups.io
<elhandjr@...>
wrote:
On Tue, Nov 19, 2024, at 01:10
PM, Richard AG5M wrote:
Evan
This morning I fired up the
radio again. Very low volume,
but after half a minute, the
volume came blasting back. That
lasted for some 10 seconds, then
went low again. Stayed low.
I have touched TP1, TP2, and Pin
3 of the LM386. I hear a faint
hum at TP1, slightly louder at
TP2, and a very nice loud hum at
Pin 3. So, it's not in the audio
chain - would that be right? If
right, where to look next? Time
to bring out the freq counter
and Oscope?
73, Richard AG5M
?
Was that TP1 and TP2, or TP21 and
TP20?? All are on the board.? TP1
tests the antenna input, TP20 tests
the audio after the demodulator, and
TP21 is the input to the audio amp
with muting.
?
?
With the volume control fully
clockwise, the AC hum should be the
same when touching pin 3 of the
LM386 as TP21.? If not, then there
may be an issue with the volume
control.? Try turning it back and
forth to see if there is a broken
connection.
?
Another test is to verify that
the mute MOSFET (Q74) is switching
correctly.? Measure the gate voltage
of Q74.? It should be zero when
receiving and 5 volts when
transmitting.? Also, you can measure
the resistance from TP20 to ground
with the radio on.? It should be
higher than 5kOhms while receiving
and less than 200 Ohms when
transmitting.? If not, then Q74 may
be bad.
?
Another problem I have seen with
low signal strength is related to
the Raduino board.? The Si5351 chip
failed to lock at the right
frequency, which would appear as a
jittery signal on any of the three
clocks to the mixers and
demodulator.? In particular, the BFO
seems to drop in and out of sync.?
This could be the case for any of
the three clock signals.? To test
the Raduino, I removed it from the
radio, powered it from a USB
connection to my PC, and measured
the outputs on the mainboard
connection.
?
73
Evan
AC9TU
?
_._,_._,
|
Re: uBITX v6 Low Audio Update 11-23-24
The process of finding something that¡¯s wrong is one of breaking the system down and into modules and then testing each module. ?
That¡¯s part of the skill set that we expect to develop in a cadre of technically experienced people as the goal of FCC part 97.1. ??
It¡¯s a good thing that you¡¯re getting this chance to learn. I do the same thing with my chemistry students. I got the same experience myself when as a novice I put a kit together and it didn¡¯t work. It took me months to make it work and I learned a ton in the process. ? As you could guess I did much better in my electrical engineering training.?
No one is entitled to help here. ?Be grateful for the people who are giving you their time and as long as you are making progress, others will stand in the wings for the moment.
There is a reason that this is called amateur radio.
We are the only service that is allowed to repair their own radios. And the price for that is that you¡¯re expected to learn things.
So move forward and enjoy! ? you will eventually figure it out just as we all have with the various problems we had with our radios. ??
Best regards,
Gordon kx4z?
toggle quoted message
Show quoted text
On Nov 23, 2024, at 20:35, barry halterman via groups.io <kthreebo@...> wrote:
? Richard, I figured you might have done that already, but I put that out there. Justin Case. Yes, you need to get a scope on there and see at what point your losing the signal.
Frustrating it can be but look at the knowledge you will gain.?
Personally, I have cut and hacked a V4 and a V6 and learned a great deal. Sorry I cannot be of further assistance.
Barry
|
Juan,
That is already a software feature in the sbitx. We won't have to add it
Ashhar,?
?
What about a headless trx and operate from phome/tablet/pc etc.
?
Juan
|
Re: uBITX v6 Low Audio Update 11-23-24
Richard, I figured you might have done that already, but I put that out there. Justin Case. Yes, you need to get a scope on there and see at what point your losing the signal.
Frustrating it can be but look at the knowledge you will gain.?
Personally, I have cut and hacked a V4 and a V6 and learned a great deal. Sorry I cannot be of further assistance.
Barry
|
Re: uBITX v6 Low Audio Update 11-23-24
Thank you Barry.
I have tapped and prodded until the cows come home. Was hoping for something but nothing, but it's really solid. Apparently not an easy fix, so so it seems at the moment.
73, Richard AG5M
On Saturday, November 23, 2024 at 04:34:37 PM PST, barry halterman via groups.io <kthreebo@...> wrote:
Richard, there are a multitude of possible locations where you are losing the audio. If it pops up normal, then goes down, I would suspect a bad solder joint with one of the SMD parts in the receive IF amps, filter and even the transformers might not have a good solder connection. My V4 was very noisy when tapping on some of the ceramic SMD coupling caps, possible you have one that is bad or poorly soldered. If you have not tried to tap on some of the parts to see if you are getting noise, that might help to locate the problem area. ? GL ?Barry
|
Re: uBITX v6 Low Audio Update 11-23-24
Richard, there are a multitude of possible locations where you are losing the audio. If it pops up normal, then goes down, I would suspect a bad solder joint with one of the SMD parts in the receive IF amps, filter and even the transformers might not have a good solder connection.
My V4 was very noisy when tapping on some of the ceramic SMD coupling caps, possible you have one that is bad or poorly soldered. If you have not tried to tap on some of the parts to see if you are getting noise, that might help to locate the problem area.
?
GL
?Barry
|
Re: uBITX v6 Low Audio Update 11-23-24
Richard, there r many of these radios on the air. I have two myself and love them.
You are working with one of the best (Evan) to get yours up and running. Keep up the good work and look forward to hearing you on air.
73 KI4QCK
toggle quoted message
Show quoted text
On Nov 23, 2024, at 6:51?PM, Richard AG5M via groups.io <ag5m@...> wrote:
? Thanks Evan, I'll give it a go.
I know the original owner, my dear friend who went SK, did try to do an alignment but never could get it to work right. I'll try and let you know how it goes.
Interesting, so far you are the only person who has responded to my plea for help. Must not be many Hams around who know anything about this radio.
73, Richard AG5M
On Saturday, November 23, 2024 at 11:16:36 AM PST, Evan Hand via groups.io <elhandjr@...> wrote:
On Sat, Nov 23, 2024, at 01:00 PM, Richard AG5M wrote: So according to what you (Evan) said, that's right. Everything is right so far, but I have weak audio. Hi Richard, ? Yes, those readings at TP21 are good.? The problem is not with RX muting when not transmitting. ? The v6 uBiTx schematic is here: And here for the Raduino board: ? Both are from the HFSignals web page: ? The next step that I would try is the BFO calibration using an audio spectrum analyzer like this one: ? The process is in this video: ? You do not need to complete the entire calibration process; just check the last step, the BFO final adjustment at 9:40 into the video.? If the Raduino Si5351 has problems, you cannot tune in to the plateau peak.? If this test fails, break out the scope and/or frequency counter. ? 73 Evan AC9TU ? ? ?
|
I would also like to know where the best place to grab the power for the ATU. Did you add a component, or just tap into an existing rail?
--
Kris
kris@...
toggle quoted message
Show quoted text
On Sun, May 19, 2024, at 4:06 PM, Aaron K5ATG wrote: How did you get the 12 volts to run the ATU?
I have a couple of those tuners around that don't have cases for them
and would be perfect for an internal ATU for the sBITX
--
'72
Aaron K5ATG <>
|
Re: uBITX v6 Low Audio Update 11-23-24
Richard
?
If you spend some more time in the group, or read back into the massive volume of posts to it, you will find there are a great number of Hams who know a very great deal about this radio, including the designer Ashhar who appears regularly. I have been a member now for some years and have found the group one of life's great learning environments.
?
I would also suggest you do a little research into the background of HF Sigs to better understand the nature of that operation. We are not dealing with big corporations who manufacture and sell black boxes here.
?
?
Bill VK7MX
|
Re: uBITX v6 Low Audio Update 11-23-24
Thanks Evan, I'll give it a go.
I know the original owner, my dear friend who went SK, did try to do an alignment but never could get it to work right. I'll try and let you know how it goes.
Interesting, so far you are the only person who has responded to my plea for help. Must not be many Hams around who know anything about this radio.
73, Richard AG5M
On Saturday, November 23, 2024 at 11:16:36 AM PST, Evan Hand via groups.io <elhandjr@...> wrote:
On Sat, Nov 23, 2024, at 01:00 PM, Richard AG5M wrote: So according to what you (Evan) said, that's right. Everything is right so far, but I have weak audio. Hi Richard, ? Yes, those readings at TP21 are good.? The problem is not with RX muting when not transmitting. ? The v6 uBiTx schematic is here: And here for the Raduino board: ? Both are from the HFSignals web page: ? The next step that I would try is the BFO calibration using an audio spectrum analyzer like this one: ? The process is in this video: ? You do not need to complete the entire calibration process; just check the last step, the BFO final adjustment at 9:40 into the video.? If the Raduino Si5351 has problems, you cannot tune in to the plateau peak.? If this test fails, break out the scope and/or frequency counter. ? 73 Evan AC9TU ? ? ?
|
Re: uBITX v6 Low Audio Update 11-23-24
On Sat, Nov 23, 2024, at 01:00 PM, Richard AG5M wrote:
So according to what you (Evan) said, that's right. Everything is right so far, but I have weak audio.
Hi Richard,
?
Yes, those readings at TP21 are good.? The problem is not with RX muting when not transmitting.
?
The v6 uBiTx schematic is here:
And here for the Raduino board:
?
Both are from the HFSignals web page:
?
The next step that I would try is the BFO calibration using an audio spectrum analyzer like this one:
?
The process is in this video:
?
You do not need to complete the entire calibration process; just check the last step, the BFO final adjustment at 9:40 into the video.? If the Raduino Si5351 has problems, you cannot tune in to the plateau peak.? If this test fails, break out the scope and/or frequency counter.
?
73
Evan
AC9TU
?
?
?
|
Re: uBITX v6 Low Audio Update 11-23-24
Tried again this morning, this time on the correct TP, TP21. I have 53.6K on RX, 2.1 ohm on TX. So according to what you (Evan) said, that's right. Everything is right so far, but I have weak audio.
Time to get out the O-Scope? I do not have a schematic, does anyone have one? I used it this morning to check into the Noon-Time-Net with CW so other than weak audio it appears to be working FB. BTW, is there a setting to reduce the sidetone level? It's really loud!
I'm surprised that other than through this Forum, HFsignals provides no support. Makes me a little hesitant to purchase a radio from them. Given this experience.
73, Richard AG5M
On Friday, November 22, 2024 at 02:55:55 PM PST, Richard AG5M via groups.io <ag5m@...> wrote:
Taking another run at this, I confirm I have Zero volts RX at the gate of Q74, if the gate pin is the one closest to D14. And I have 5 volts when in TX mode. Given this information and what's noted below, dos this tell anyone anything? Why I have virtually no audio?
73, Richard AG5M
On Thursday, November 21, 2024 at 11:03:28 AM PST, Richard AG5M via groups.io <ag5m@...> wrote:
Evan and others who may be following.
The TP1 and TP2 I mentioned below was a typo, they were TP20 and TP21. I did the same this morning. With volume control fully clockwise. Nice loud hum at Pin 3. Considerably lower hum at TP21, and almost no hum at TP21. Turning the volume control made difference.
This morning I checked the resistance measurements you mentioned at TP20. With radio on it measured 70 ohms RX, 2.36K TX. From what you mentioned then I guess Q74 is faulty? I did not make voltage measurement yet. Where exactly is Q74? I don't see it.
73, Richard AG5M
On Tuesday, November 19, 2024 at 05:09:11 PM PST, Evan Hand via groups.io <elhandjr@...> wrote:
On Tue, Nov 19, 2024, at 01:10 PM, Richard AG5M wrote: Evan
This morning I fired up the radio again. Very low volume, but after half a minute, the volume came blasting back. That lasted for some 10 seconds, then went low again. Stayed low.
I have touched TP1, TP2, and Pin 3 of the LM386. I hear a faint hum at TP1, slightly louder at TP2, and a very nice loud hum at Pin 3. So, it's not in the audio chain - would that be right? If right, where to look next? Time to bring out the freq counter and Oscope?
73, Richard AG5M ?
Was that TP1 and TP2, or TP21 and TP20?? All are on the board.? TP1 tests the antenna input, TP20 tests the audio after the demodulator, and TP21 is the input to the audio amp with muting. ? ? With the volume control fully clockwise, the AC hum should be the same when touching pin 3 of the LM386 as TP21.? If not, then there may be an issue with the volume control.? Try turning it back and forth to see if there is a broken connection. ? Another test is to verify that the mute MOSFET (Q74) is switching correctly.? Measure the gate voltage of Q74.? It should be zero when receiving and 5 volts when transmitting.? Also, you can measure the resistance from TP20 to ground with the radio on.? It should be higher than 5kOhms while receiving and less than 200 Ohms when transmitting.? If not, then Q74 may be bad. ? Another problem I have seen with low signal strength is related to the Raduino board.? The Si5351 chip failed to lock at the right frequency, which would appear as a jittery signal on any of the three clocks to the mixers and demodulator.? In particular, the BFO seems to drop in and out of sync.? This could be the case for any of the three clock signals.? To test the Raduino, I removed it from the radio, powered it from a USB connection to my PC, and measured the outputs on the mainboard connection. ? 73 Evan AC9TU ?
|
Ashhar,?
?
What about a headless trx and operate from phome/tablet/pc etc.
?
Juan
|
?Bitx concept as a pure receiver
Can the concept of the ?Bitx be used with the SIS5351 as a
solo receiver.
I would like to build a receiver based on this concept. Either with 12MHZ or with 11Mhz crystals I have for both versions.
Has anyone used this before and is there any information about it?
?
Many Thanks Bernd DL3BLA
|
Well, I wouldnt wager on that. Though, getting a display to survive a drop test will be tough. The rest of electronics will take knocks and bumps with ease.
2. Are you planning 'Drop Tests' as they do it for mobile phones? 5 V operation from a power bank would be an excellent idea. On Sat, Nov 23, 2024 at 6:09?PM Ashhar Farhan via <farhanbox= [email protected]> wrote: Zero has more than ample power to run all the core modems and more.
I would also add to the list, my own desireables:
1. 5v operation from a power bank
2. Ability to withstand knocks and drops.
3. Low cost. I cant afford a 1000 usd KH1.
A Zero might be too constrained. Better a B model - or a carrier board to support the compute modules - which might afford upgradability?
|
2. Are you planning 'Drop Tests' as they do it for mobile phones? 5 V operation from a power bank would be an excellent idea.
On Sat, Nov 23, 2024 at 6:09?PM Ashhar Farhan via <farhanbox= [email protected]> wrote: Zero has more than ample power to run all the core modems and more.
I would also add to the list, my own desireables:
1. 5v operation from a power bank
2. Ability to withstand knocks and drops.
3. Low cost. I cant afford a 1000 usd KH1.
A Zero might be too constrained. Better a B model - or a carrier board to support the compute modules - which might afford upgradability?
|
Zero has more than ample power to run all the core modems and more.
I would also add to the list, my own desireables:
1. 5v operation from a power bank
2. Ability to withstand knocks and drops.
3. Low cost. I cant afford a 1000 usd KH1.
A Zero might be too constrained. Better a B model - or a carrier board to support the compute modules - which might afford upgradability?
|
A Zero might be too constrained. Better a B model - or a carrier board to support the compute modules - which might afford upgradability?
|
Re: uBITX v6 Low Audio Update 11-22-24
I just checked their webpage. Apparently the only support they offer is this forum here on [email protected]. 73, Richard AG5M On Friday, November 22, 2024 at 05:30:28 PM PST, Evan Hand via groups.io <elhandjr@...> wrote:
Richard, ? I do not know about HFSignals support.? I would try again.? They have had server issues in the past. ? 73 Evan AC9TU ?
|
Re: uBITX v6 Low Audio Update 11-22-24
Richard,
?
I do not know about HFSignals support.? I would try again.? They have had server issues in the past.
?
73
Evan
AC9TU
?
|
Raj vu2zap
Richard AG5M
Kris
4Z4DR