Mic audio and TX power mods required with V6?
Hello,
I've recently purchased a V6 and was wondering if it's still recommended that one do the microphone audio mod that involves paralleling a 10 ohm resistor across R63 as well as the RF power equalization mod as described here: (/g/BITX20/topic/transmitter_mods/17458699?p=Created,,,20,1,80,0&jump=1)
I wanted to ask before I started modifications as perhaps one or both of the issues may have already been resolved on the V6 board.
Thank you,
- Mike
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I assembled my new UBITX V6.1 about two weeks ago and have a problem with my CW signal being off frequency. Calibration seems correct since I can make SSB (LSB/USB) contacts with no problem. I have verified with a FTDX 5000 transceiver that the transmitted signal is about 800 hertz below the received signal. The "RIT" and "SPL" buttons are off. Only the USB/CW or LSB/CW buttons are lit based on the band. An amazing little rig otherwise. Hopefully someone knows what to do next.?
73's,
Jerry W9KTP
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Hi,
I was going to say that I have casually added some mods on my V3. Without a spectrum analyzer (yet) I just use outboard, additional filters - a la the olden dayes. I use mine for CW through 17 meters. I will address the relays, harmonics, and spurii when I get my Spectrum analyzer. Apparently this one has already been done:)
73,
Bill KU8H
bark less - wag more
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On 7/14/20 10:57 AM, Joel Caulkins/N6ALT wrote: Hi Chris,
I had done several of the 'spurs' mods that were popular at the time to that radio before I sent it to you, it was putting out at least 10 watts on most bands and I used it it regularly to check into 40 and 20 meter nets and to make random QSOs. I know it's fun to mod these radios, but if you did absolutely nothing to it, it should work perfectly for you. I'm not trying to discourage you from doing the mods, I'm just letting you know what I have done before you got it. What ever you do, have fun! BTW, those 2N2222A's you got look great, the 2N2222A is the backbone of Ham radio.
Joel
N6ALT
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Nextion display in ubitx V6
Attached is a picture of my ubitx V6 outfitted with a 2.8 inch, nextion display. A little history with my V6.
I was having issues with tuning clicks or more like chugging noises, especially on 20 meters. To a lesser extent on 40. This was very annoying!
I replaced the nano and TFT display, etc....still had those clicks. So, I got a nextion display and temporarily hooked it up. All tuning artifacts gone.
Someone had posted on here about using a nextion on the V6 and only using two screws. Sorry can't remember who, but you can use four screws to mount the 2.8 inch display. Just file the existing countersunk holes on the left side of the left holes and the right side of the right holes. I used the original spacers from the TFT display and separated the radrino from the display. The radrino is free and doesn't get pulled when mounting the display.i used 3 x 6 mm screws and 3 x 9 mm fender washers, that I painted black, to mount the display. If you ever want to go back to the TFT display just use the same new screws and washers.?
One thing I do like about the nextion display is I can read the frequency across my workbench, something I could not do with the TFT display. More importantly is no more darn tuning artifacts!!
Barry
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Hi Chris,
I had done several of the 'spurs' mods that were popular at the time to that radio before I sent it to you, it was putting out at least 10 watts on most bands and I used it it regularly to check into 40 and 20 meter nets and to make random QSOs. I know it's fun to mod these radios, but if you did absolutely nothing to it, it should work perfectly for you. I'm not trying to discourage you from doing the mods, I'm just letting you know what I have done before you got it. What ever you do, have fun! BTW, those 2N2222A's you got look great, the 2N2222A is the backbone of Ham radio.
Joel
N6ALT
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Re: ubitx v6 TX problem with FT8 on 3 bands
Thank you all for the great responses!? The quick dummy load test worked fine.? So when I get a chance, I need to resolve the RF problem affecting the Nano.
Tom
AB7WT
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Indeed this is most helpful. The load kit I have has an rf probe built in and the general power readings will help. The heat sinks probably won¡¯t matter unless my antenna works and I can do digital modes :).
That being said I am just trying to get on Hf now. I don¡¯t even know if my v3 is tuned up and if I need to filter it so I am quiet for now. Once the parts get in I will go to town.
KF4FTR
On Tue, Jul 14, 2020 at 4:54 AM Bob Fischer, Fischer Technical Services < FischerTek@...> wrote:
I installed 2N2222A transistors in my Build #3.? Did not add the heat sinks but they shouldn't hurt anything. I also soldered another 22 Ohm resistor in parallel with each of the emitter resistors. Build #3 Notes attached.
You might also be interested in the simple Q90 modification results I got from the build I am working on now: uBITX Build #5? ? July 2020 ?????using V3 board? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Original Transmit Power into dummy load @ 13.7VDC:? ? ? ? ? 80M = 20W, 40M = 14.5W, 20M = 8.5W?? 17M = 3.5W?? 15M = 1.8W?? 10M = 0.75W WB8BEL Modifications: 1. Increased the gain of Q90 transmitter amplifier: Shorted emitter resistor R83 New Transmit Power @ 13.7VDC: 80M = 20W, 40M = 16W, 20M = 14W? ? 17M = 5W? ? ?15M = 3W? ? ? 10M = 1.5W
Good Luck. Bob
Hello,
I just purchased a half dozen 2n2222A transistors from mouser with heat sinks.
I would just like to verify I purchased the right transistors and heat sinks for my v3 are correct.
Chris
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Re: Case Measurements uBITX v6
Thanks Reed. It appears that the actual case is 3 1/8" high. I appreciate your help.
Bob, N1KPR
NOTE Pls add backup address to your phone book: rwbetts@...
http://www.bobsamerica.com? http://www.youtube.com/n1kpr
Engineering: Where Enigma meets Paradox
On Monday, July 13, 2020, 10:02:20 PM EDT, Bill Cromwell <wrcromwell@...> wrote:
Hi Reed,
I was going to point out that without the feet it will fit in that 3.5
inch height. I hope it is not too wide to fit a rack <evil grin>.
73,
Bill? KU8H
bark less - wag more
On 7/13/20 9:28 PM, Reed N wrote:
> Also note that the feet are optional.
>
>
> Reed
>
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John,
Actually there are two 7805 types of regulators in the uBITX design.? One as you pointed out supplies the Raduino.? The other is an SMD version soldered on the mainboard for the bias voltage on the finals (in the blue box of the screen shot of a section of the uBITX schematic).? That one is the one that I asked for the measurements.??
Still, I agree that it is a strange coincedence that the difference is 5Vdc.
Aaron,
The voltage measurements should be made in refference to the supply negative, any of the ground points on the connectors like the shiled of the BNC RF connector.? Another point would be pin 3 of the P1 power connector that is not used.
73
Evan
AC9TU
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Re: ubitx v6 TX problem with FT8 on 3 bands
Tom,
I would try using a dummy load as the antenna. ?If the problem goes away it is most likely rf getting into the Nano Control. ?I had that issue with an OCFD. ?Solved by putting snap on ferrites on the USB and audio cables.?
You might also want to check audio levels. Overdriving the audio makes the problem worse.?
Just some ideas to try.?
73
Evan
AC9TU
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Evan, Aaron,
Since the unit is described as working and we know that 7.87V on the output of the regulator would mean death to the Raduino it must be the reference point of the measurement.?
Is it a coincidence that 12.85 - 7.87 is virtually 5Vdc, or was the measurement done from the positive as reference instead of the negative?
73? John (VK2ETA)
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I installed 2N2222A transistors in my Build #3.? Did not add the heat sinks but they shouldn't hurt anything. I also soldered another 22 Ohm resistor in parallel with each of the emitter resistors. Build #3 Notes attached.
You might also be interested in the simple Q90 modification results I got from the build I am working on now: uBITX Build #5? ? July 2020 ?????using V3 board? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Original Transmit Power into dummy load @ 13.7VDC:? ? ? ? ? 80M = 20W, 40M = 14.5W, 20M = 8.5W?? 17M = 3.5W?? 15M = 1.8W?? 10M = 0.75W WB8BEL Modifications: 1. Increased the gain of Q90 transmitter amplifier: Shorted emitter resistor R83 New Transmit Power @ 13.7VDC: 80M = 20W, 40M = 16W, 20M = 14W? ? 17M = 5W? ? ?15M = 3W? ? ? 10M = 1.5W
Good Luck. Bob
From: "Christopher Miller" <djmalak2k6@...> To: [email protected]Sent: Tuesday, July 14, 2020 7:23:14 AM Subject: [BITX20] 2N2222A upgrade
Hello,
I just purchased a half dozen 2n2222A transistors from mouser with heat sinks.
I would just like to verify I purchased the right transistors and heat sinks for my v3 are correct.
Chris
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Hello,
I just purchased a half dozen 2n2222A transistors from mouser with heat sinks.
I would just like to verify I purchased the right transistors and heat sinks for my v3 are correct.
Chris
|
Re: UBITX V4 for sale
#v4
Would you ship to Australia?? 73
Paul VK2FPAD
V4 with mods to add JackAl board. All parts that come with it, and W0EB Raduino clone.
$80 OBO?
mike
AI4NS
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Re: ubitx v6 TX problem with FT8 on 3 bands
I have been using FT8 with my uBitX with CEC software for some time on those bands.
However when I upgraded to WSJT-X 2.2.2 the cat control stopped working. Apparently there is a bug in WSJT-X and it might work if you set it for FT-857 although I went back to using version 2.2.0
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Re: ubitx v6 TX problem with FT8 on 3 bands
Hi Tom,
You might try loading my build on there. No hardware mods, but I did just test R1.5.0 with WSJT-X v2.1.2 and was able to transmit multiple cycles.
If you have the same problem running my build, then my next bet would be that somehow the RF is getting back into your rig and messing with the Nano's operation, locking it up or something.
Reed
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ubitx v6 TX problem with FT8 on 3 bands
New ubitx v6 with stock firmware works fine with FT8 on all but 3 bands.? 10m, 12m, 15m, 17m, 20m, & 40m all work fine (even 160m works fine with external LPF).? But 30m, 60m, & 80m won't TX correctly with WSJT-X for me.? Has anyone else successfully done FT8 on those 3 bands?? My problem is the same on all 3 bands.? TUNE works fine with TX.? But TX works once with TX light and power output.? But at the end of the TX duty cycle, output power stops (as it should), but the TX light stays on continually and output power never comes on again.? Unplug USB & power off/on just repeats symptom.? TUNE fine but regular TX only once.? Just 30m, 60m, 80m with problem.? DEBUG#1: Turn off radio & watch TX light.? TX goes on and off correctly with each TX & RX duty cycle (obviously no power out).? Works correctly until you turn on radio, then "lock up" behavior starts again.? DEBUG#2: Swap out new v6 radio with an older ubitx v3 & Ian's firmware and it works fine on those 3 bands with same WSJT-X software.? Older ubitx works on all bands.? I haven't had a chance to do DEBUG#3 yet: change out v6 display to Nextion & load Ian's firmware.? I was just wondering if anyone else has seen this issue?? Or if I'm missing something obvious?
Thanks!
Tom
AB7WT
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Re: Case Measurements uBITX v6
Hi Reed,
I was going to point out that without the feet it will fit in that 3.5 inch height. I hope it is not too wide to fit a rack <evil grin>.
73,
Bill KU8H
bark less - wag more
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On 7/13/20 9:28 PM, Reed N wrote: Also note that the feet are optional.
Reed
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Re: Case Measurements uBITX v6
Also note that the feet are optional.
Reed
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Re: Case Measurements uBITX v6
Maybe this pic will help. Reed 
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Joel Caulkins/N6ALT
Bob, N1KPR
Mike G4GOU