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That hurts (I've been there)!? I lost all of my equipment (except for one radio and some parts) back in 2010, when someone got angry at a letter to the editor I'd written and torched my electronics workshop/home laboratory.? (I'm still working on recovering.)? I've also had vehicles destroyed in accidents, and because of the county (never informed me of the court date when a woman hit me head-on while driving in the wrong lane - she got the ticket for it but it was all dropped "because you didn't show!!!") took a total loss on the vehicle.? (A clue about my driving skill and history - over 1.2 million miles driven with no at-fault accidents in the last 35 years.)

I hope you can find the resources to get back on your feet very soon.? The longer you have to wait, the more it hurts.

Good luck!? I'm hoping the best for you - and that the impact to your life becomes minimal!

Bob

N4FBZ

I agree with Jerry -- the Harbor Fright DVMs are the ones I reach for first.?

?

Like Jerry, I do that because they are cheap crap and I don't care if I blow one up.? Having set fire to the same Fluke 77 three times, I agree, blow up the cheap junk first.? I will mention that Fluke has always been more than generous on repair or upgrade replacement on my 77s.? So they're high on my "use vendor again" list.?

I'll also add -- the ME-77C/U mil-surplus multimeter (google iot) is on my "maybe you don't want to buy this again, because it uses a $75 unobtainium 22.5 V battery that can't be replicated from current sources.? But if I could get one to work ... I'd put it out on my Field Day table for testing stuff.? And then I'd get a few more.

Why?? Because everybody around here (Austin TX, within shouting distance of all the airbases in San Antonio) we see a lot of these in the junk boxes at swap fests, and they're kinda the 1950s version of the crap Harbor Fright DVMs.? Most of the gentlemen who used to use these have passed, but there are a few of us who still recognize classic utility.

73
Jim N6OTQ

PS -- Good off-list stuff at <https://armypubs.army.mil/>

Wayne this really is bad news.? Were you able to save anything else?
--

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One thing to keep in mind with a DVM is it’s safety rating. Should a transient voltage hit the meter you want the meter to be able to interrupt the internal fault and protect the user with adequate insulation in the probes, leads, and case. At minimum you should look for a Cat 1 rating. Here is some info from Fluke>>

Thanks everyone for the ideas and feedback - some much needed nicer weather this weekend led to yardwork instead of "playing" so I haven't had a chance to
get back to it - will update again soon - but wanted to let y'all know I appreciate the help.

K B 8 H B F

Hello Sascha,

I can look at this later this week as I am pretty busy right now. Sorry for that.

73, John (VK2ETA)

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I would like one please.?

Hi everybody,

the missing bracket was not the solution - in fact it did nothing at all.

I assume it is not the right position in the function, but I cant really imagine why this is so. The position seems plausible.
But I have to admit i do not understand in detail how the function works. It is a bit "nested" .

void CatSetPTT(boolean isPTTOn, byte fromType)
{
? //
? if ((!inTx) && (fromType == 2 || fromType == 3)) {
??? Serial.write(ACK);?
??? return;?
? }
?
? // Set PTT Mode
? if (isPTTOn)
? {
??? if (!inTx)
??? {
????? txCAT = true;
????????????? if (isAM == 0)
????????????? {
??????????????????? startTx(TX_SSB, 1);
????????????? }
????????????? else? {startTx(TX_CW, 1);
??????????????????? cwKeydown();
??????????????????? }
????? //Exit menu, Memory Keyer... ETC
????? if (isCWAutoMode > 0) {
????????????????????????????? isCWAutoMode = 0;
????????????????????????????? printLineF2(F("AutoKey Exit/CAT"));
???????????????????????????? //delay_background(1000, 0);
???????????????????????????? }
??? }
? }
?
? else // without PTT
? {
??? if (inTx)
??? {
???? // cwKeyUp(); was not working
????? stopTx();
????? txCAT = false;
??? }
? }

? Serial.write(ACK);

I tried something else then, I smuggled the cwKeyUp() then into the CatSetMode-function.
So everytime a new mode is selected (which happens after tuning mode), the CWkey gets lifted. I do not know if this has side effects, but at least it seems to work.

Shamefully this solves only the problem with the sidetone after pressing the Tune-Botton, not the issue with the interrupted TX-Mode

This is the persisting issue:

If the transmitter is switched on via CAT-Signal by the loop Controller (either via PC command or by pushing the tune botton), the triggered TX-Mode is always stopped
again after about 1,3 seconds.

This time I think the problem is the Loop Controller - because it seems to be intentional. Or at least this can be assumed by looking at the serial protocol of the Teensy.

The controller sends the AM -Mode and PTT command to the uBitx.? The TRX starts sending HF and after about 1,3 to 1,5 seconds it switches back to RX AND also
the previously active mode.

I have checked with another tranceiver and an addional SWR-Meter. There is really HF coming out, but the reason for stopping is absolutley unclear to me.

Maybe there is a failsafe procedure I do not find - or the loop lontroller expects a kind of feedback signal from the tranceiver. I have also already tried to increase the delay
after the TX-Start and the SWR measurement (assuming the signal needed to be on longer), but this was also fruitless.






I think the procdure of the tuning process is this:

Maybe somebody has an idea.

73s

Sascha

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I've got about 10 of the HF dvm's lying about,
I do have better, but the HF are generally the first dvm I reach for.
Mostly because there is likely to be one close at hand.

I've never found accuracy to be an issue, they are extremely accurate.
A capacitance range would be nice, and auto ranging can be handy too.
Probe wires separate from the probes after a few months of hard use, easy to fix.
My primary issue is the HF dvm's seem easier to destroy than
some of the other dvm's, doing stupid stuff like having the dvm set to ohms
when looking at a voltage source.? Especially when??probing stuff out in the rain
at night when the pickup has an electrical failure or something.? And in that case
it would always be the HF, since I have one in the glovebox.

When I do pop one, it's a very cheap $1.00 (on sale) lesson.
Not a $100 one.

Good idea to color the business end of the knob so you don't accidentally?
have it turned 180 degrees from what you want.

Jerry, KE7ER
??

Mark,
I'm hardly an expert at what I'm doing so, I can't be too far ahead of you.

With your signal generator and voltmeter you ought to be able to make the same measurements I have. Give us some idea of what first baby steps need help with. I don't know the HP8640b but I can try to help with where to connect and take measurements.

-- digger AB3XU?

Tim,
Had a chance last night to make some more measurements. Hopefully we are the same page now.

I made two sets of measurements to look at the difference between taking the audio on the ubitx on either side of R70 -- vol-h and TP21. Also curious I made them with USB and LSB. So.....

Sark 110 (7.101Mhz) --> ubitx (7.099.7 USB)
???? vol-h --> AGC, vol-h
???? TP21 --> 11.4ohm --> AGC, vol-h

Sark 110 (7.100Mhz) --> ubitx (7.100.7 LSB)
???? vol-h --> AGC, vol-h
???? TP21 --> 11.4ohm --> AGC, vol-h

That tuning on the ubitx gets a tone very close to 1K. (i guess that means I need to adjust the BFO by about 300Hz)
The resister is 11.4 ohms - my other choice was 9ohms.
AGC was in the middle/slow position.

The measurements I'm getting with using TP21 for the input to the AGC still seem lower by about half than what is expected based on ND6T's circuit theory and numbers he posted in another thread.

ADC Comparison of ND6T's numbers and my readings from CEC firmware
RF???????? ND6T??? mine
S9?????????? 170???????? 84
S9+10??? ?? -????????? 170
S9+20???? 300??????? 200
S9+30?????? -?????????? 297
S9+40???? 700??????? 399
S9+50???? 800??????? 517

I hope this all makes sense! Let me know if anything need interpretation!
I would really like to see some measurements made with another V4.

I disagree with his hate for cheap/free Harbor Freight multimeters.? Sure they're not nuclear grade accurate but for a ham on a budget they have their place.? Besides, it is most likely more accurate than the tolerances of the components being tested.
--

Hi Mike,?

How did you get the issue away and what was the main issue or main reason for your low output ?

This is an very difficult thing in same style problem what i have with my ubitx and i dont find a way to become more than 4-5 Watts on 80m an on each other it was evertime less with higher frequency.. on 10m only 1 Watt and this is not the real way to operate with this low output, so i was very thankfull for any answer, thanks !

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Thank you so very much. For myself this one post would make it worth joining even if no one ever helped a fellow Han and the the whole group was grumpy old men. But NO, this is just the opposite. A bit of good humor goes a long way even on a good day.?
Qualifications:
electronics study, build, repair, design, & modify since 1950.?
USMC trained telephone, radio, fader, & test equipment use/calibration.
Design/build 2 kw amp using military salvage dental equipment power supply for K4MCL/N0AMC Albany, Ga.?
IBM trained computer hardware, software, and senior programmer vi editor.

Future:
7 inch display for ubitx v4 with wireless remote control using no machine/teamviewer software.?
System boxed for use with Terratrike when trail riding.?

Frank KJ5WI, the wild Indian

Lol...typed on my phone so it's Google's guys in that case, but the same issue. Even changes the word when the spelling is right...trying to be smart but not smart enough.