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)
|
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
|
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
toggle quoted message
Show quoted text
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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Case Measurements uBITX v6
Our club is considering several of these xcievers for our emergency team members. One will be rack mounted in a van and another permanently installed in a rack at the Comm Center and one or two more will be portable. A 2RU rack will accommodate a 3.5" height. Would someone be kind enough to tell me the overall height of the standard uBITX v6 cabinet?
I'll post the progress of our builds here. These will probably include built-in tuner, preselector with BCB switchable stop filter, and an enhanced audio section.
Thanks in advance.
Bob, N1KPR
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Most should know this but do not try to measure voltages on the power out amp transistors and key the transmitter at the same time. I did this once on an MFJ 40M SSB QRP rig, across a choke, and the meter became a pretty memory. RF voltages are much higher than one may imagine.
Bob ¡ª KK5R
On Monday, July 13, 2020, 2:21:53 PM EDT, Aaron K5ATG via groups.io <k5atg@...> wrote:
Here are the measurements that I have.? INPUT: 7.87
OUTPUT: 12.85
That may be backward as to what you were wanting, I determined the pins from the datasheet that I found here:? I could not test the IRF510 PA MOSFETs because it was this time that gravity decided to ruthlessly attack my multimeter and hurled it to the floor and breaking it. I hope to have a new meter by the end of the day and I will test the IR510 PA MOSFETs then.? -- '72
Aaron Scott
QRPARCI# 16443
GQRP# 16389
4SQRP # 1080
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hello. I try both..? Last, with this faults..
? Error at line 1049 in file ubitx_tft_320240.ino:
? 'class TFT_eSPI' has no member named 'getTouch'
?
Compiling Failed
regards Ken
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I will assume that you have the input and output measurements reversed. Even with that modification, the output pin of U2 (the 78Lo5ACZ) should be 5volts +/- 0.15volt.? There is something wrong with either your measurement, the regulator is bad, or there is something else pulling the voltage higher than it should be.? It is a surface mount device, so tricky to replace without a hot air surface mount rework station.
As far as I can tell, the input is to the right of U2, and the output is to the left as shown in the board picture I sent before.? The center pin is at ground, 0volts.
You can measure the drains of the IRF510s on the large tab connected to the heatsinks.? The 12volts is there all of the time.? You do not need to key the PTT switch to take the measurement.? Switching the gate bias off puts them in a high resistance mode, such that only a few milliamps of current is drawn for both of the devices.
Double-check the U2 voltages.? If you are truly getting almost 8 volts on the output of the regulator there is something really wrong with the circuit.? My only suggestion is to order a replacement before you try to remove it for testing.? When ordering get the IRF510s as well.? I believe that you will need to pull them to verify that they do not have a drain to gate short that is pulling the regulator output up.? Do this before you try to remove U2.? If that is the cause of the U2 output voltage being over 5volts, then with both IRF510s removed you should get 5volts on the outpput of the U2 regulator.? Replace the IRF510s if that is the case.
There are others on this board who will do the repair that have the proper tools and experience.? I have done this type of replacement once (I thought I had an issue with one of the BAT54SL used in the product detector, that is the only removal experience. I had 4 transistors to install in a filter kit that were surface mount that went well), however I am not confident on my capabilities to work on someone else's uBITX, even at no charge and the owner taking all of the risk.? The best option would be to find a nearby ham or club that could help with the measurement and problem solution.
Hope the above helps, and good luck in finding and fixing the issue.
73
Evan
AC9TU
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Joel Caulkins/N6ALT
Bob, N1KPR
Mike G4GOU
Bob Lunsford