Thanks -- my goal with the uBITX was multiband ops with mini-effort and max coverage -- simplicity.? I wasn't smart enough to know what this means is you lose low SWR numbers. But then I wasn't smart enough to know that SWR below say 4 doesn't matter much on the receive end. So if you can get the big picture and understand the interaction of large numbers of errors, you realize the approach works great.? hahah
I'm sure the uBITX doesn't like high SWRs at some point, and i know there is no fold back or power reduction/protection circuity. But it seem to do just fine at 4 (or more...I'm just saying).? And yes I pay attention to the drive levels and stay within the envelope, but there is one drive setting for all bands.? I've seen WSJT-X config setting drive level per band, and I may play with that, but the uBITX takes care of itself with one drive setting for all the bands that I can use.?
Based on what I've read, the EFHW 80-10 antennas could do even better than my DIY 80-10 OCFD as they seem to have 30m out of the box. If I wanted to just by a good solution, I'd try these guys (or similar -- there are lots of vendors)
How can you beat?80/40/30/20/17/15/12/10m with no antenna tuner? Several guys in our local radio club have them, and they seem to work.
But given a easy, reliable, effective and efficient commercial solution like a EFHW-80-10, or a marginal self made mess, I will aways pick the mess.? My old boss used to say that when success is too easy, you should put obstacles in your way, just to make victory sweeter.?
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The trouble seems to be with a pin of the dc connector. Just flow a huge blob of solder to where the picture shows. - f
I picked up a couple of SMA-BNC jumpers at the ham fest and was playing with it yesterday afternoon - here is a photo of a PWR scan of the broadcast FM band using an HT whip as an antenna - a few strong local stations show up
73,
Mike N2HTT
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Re: uBitx low signals on the speaker
V4 has lower than desirable audio gain. Add a single stage transistor before or after volume control.
It's fine with headphones.
Raj
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At 19/05/2019, you wrote: Hi Junior,
Not sure exactly what you did. I have the same symptoms. I can hear signals provided the antenna tuner is spot on but there should be substantially more audio. Reading your note I am not sure exactly what you did to fix it. Any clarification will be appreciated. Thanks Jeff
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I picked up a couple of SMA-BNC jumpers at the ham fest and was playing with it yesterday afternoon - here is a photo of a PWR scan of the broadcast FM band using an HT whip as an antenna - a few strong local stations show up
73,
Mike N2HTT
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Re: Homebrew li-ion battery pack into ubitx
VERY GOOD.? By the? way please post SOTA TUNER CIRCUIT.? I wanted to homebrew it for my uBITX V5 QRP.? De VU2UYC, Balsun from Calicut. 73s
On Mon 15 Apr, 2019, 8:42 PM Jerry Gaffke via Groups.Io, <jgaffke= [email protected]> wrote: The transformer of an EFHW? matching network matches the 50 ohm transmitter
to an expected impedance into the wire of between 2500 and 3000 ohms.
Power is Volts*Amps, or Volts*(Volts/Ohms).
At 5 Watts of RF power,? ? 5watts = Volts*Volts/3000ohms,? ?therefore? Volts = sqrt(3000*5) = 122 Volts RMS.
At 100 Watts, it's still around 548 Volts RMS, not yet kilovolts
Thanks Jerry, was helpful... & here's online calculator too :
Guys, any way can we know voltages approx across 20M traps ? excited with 25 watt...
The polyvaricons are rated for something around 100 Volts:
? ??
Generally, you can press a polyvaricon somewhat beyond 100 Volts.
A polyvaricon works at 5 Watts for an EFHW, though?an air-variable cap would be a better choice.
If an air gap does arc over, it will self-repair once the ionized air circulates out.
And an air gap capacitor has a higher Q, and thus lower losses.
The qrpkits Sota Tuner successfully uses a polyvaricon:in an EFHW tuner:
? ??
They claim a max of 5 Watts CW, 10 Watts PEP.
On 10 Watt peaks, that would be? sqrt(3000*10) = 173 Volts RMS.
Perhaps they are more concerned about heating than they are about arcing?
Anything other than a resonant EFHW will be lower impedance,
and thus lower voltages across a tuning capacitor.
Jerry, KE7ER
On Mon, Apr 15, 2019 at 12:33 AM, Sandeep Lohia wrote:
End fed 1/2 wave is a voltage fed antenna Sarma ji, there might be more then kilo volts present even with QRP at end of coil...
Therefore thin PVC variable Gang Capacitor won't help...
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Re: ?BITX V5 build complete (for now)
V5 uBITX FINISHED APPEARANCE EXCELLENT
Dear? OM NOKAI
Your uBITX V 5 is excellent.? Appreciate your work.
May God bless you.
73s
De VU2UYC, Balsun from Kerala, India.
Thanks for the kind words!
Faceplate is indeed sign material - Rowmark LaserMax - run through my laser cutter. Knobs are all 3D printed. Case is a CircuitSpecialists instrument enclosure (
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Re: uBitx low signals on the speaker
Hi Junior, Not sure exactly what you did.? I have the same symptoms.? I can hear signals provided the antenna tuner is spot on but there should be substantially more audio.? Reading your note I am not sure exactly what you did to fix it.? Any clarification will be appreciated.?? Thanks Jeff
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Re: What's a Reason for less Power Output ONLY get 4W on 80m?.., 3-4W on 40/20m, 1W on 15/12/10m
#ubitx
#ubitx-help
You mentioned "on Dummy Load only 10-11V", is that your power supply voltage when transmitting? The power output is very dependent on the voltage to the PA line, and if your power supply sags to 10-11 volts when transmitting then you will only get maybe 60% of normal power. Similarly, if you increase the voltage on the PA line youcan get more than "spec" power. It is a good idea to keep the main board voltage at 12v or less to avoid overheating the voltage regulators, but that is why there is a separate line to the final amplifier.
=VIc=
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Re: Inexpensive eBay Amplifier Kits
I suppose the sunil vu3sua is also selling these boards from his? Indian? site
On Sat, 18 May 2019, 9:44 pm Joe Puma < kd2nfc@... wrote: Do you have a link to this video?
73 Joe KD2NFC? On May 18, 2019, at 11:05 AM, KM4TRT via Groups.Io < garello@...> wrote: Hi N8DAH,
Thanks for the tip on Wa2EBY.? When I saw that GoldDregger Video had purchased the boards and done a complete build and test on the amp AND the accompanying? multi band filter, I went to FAR circuits and ordered the boards
They are 19.50 US + $3.5 shipping
Andy
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Re: What's a Reason for less Power Output ONLY get 4W on 80m?.., 3-4W on 40/20m, 1W on 15/12/10m
#ubitx
#ubitx-help
OM
how is your output power on CW?? take power readings on CW even if you don't use this mode.? this will tell us how the PA etc are working.?
some experience weak audio drive that hampers SSB transmit power - a few in our club build.? I am fortunate that using a surplus speaker microphone I had works swell, but others are not so happy.? some are adding a preamp or even a speech processor IC to their audio chain.? I think you need some patient experimenting, after affirming CW power is okay.
if you have a different microphone to try - I would.? also consider building an audio oscillator as a test source.?
73 Curt
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Re: Homebrew li-ion battery pack into ubitx
On Mon 15 Apr, 2019, 8:42 PM Jerry Gaffke via Groups.Io, <jgaffke= [email protected]> wrote: The transformer of an EFHW? matching network matches the 50 ohm transmitter
to an expected impedance into the wire of between 2500 and 3000 ohms.
Power is Volts*Amps, or Volts*(Volts/Ohms).
At 5 Watts of RF power,? ? 5watts = Volts*Volts/3000ohms,? ?therefore? Volts = sqrt(3000*5) = 122 Volts RMS.
At 100 Watts, it's still around 548 Volts RMS, not yet kilovolts
Thanks Jerry, was helpful... & here's online calculator too :
Guys, any way can we know voltages approx across 20M traps ? excited with 25 watt...
The polyvaricons are rated for something around 100 Volts:
? ??
Generally, you can press a polyvaricon somewhat beyond 100 Volts.
A polyvaricon works at 5 Watts for an EFHW, though?an air-variable cap would be a better choice.
If an air gap does arc over, it will self-repair once the ionized air circulates out.
And an air gap capacitor has a higher Q, and thus lower losses.
The qrpkits Sota Tuner successfully uses a polyvaricon:in an EFHW tuner:
? ??
They claim a max of 5 Watts CW, 10 Watts PEP.
On 10 Watt peaks, that would be? sqrt(3000*10) = 173 Volts RMS.
Perhaps they are more concerned about heating than they are about arcing?
Anything other than a resonant EFHW will be lower impedance,
and thus lower voltages across a tuning capacitor.
Jerry, KE7ER
On Mon, Apr 15, 2019 at 12:33 AM, Sandeep Lohia wrote:
End fed 1/2 wave is a voltage fed antenna Sarma ji, there might be more then kilo volts present even with QRP at end of coil...
Therefore thin PVC variable Gang Capacitor won't help...
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Congrats on turning it loose Don, those are some really nice results.? I'm envious of your antenna doing so well without a tuner.? I hadn't noticed those pie charts before, but yes 30m is a pretty good band these days, for small bandwidth work at least.??
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Re: Lista component for ubitx 5
#ubitx
Thanks exactly what I looking for......?
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Re: quick mod to USB cable to remove VCC for CAT control
Good idea. It bugs me too when I power off the radio and the raduino is still on. It powers the radio too because when I have my pan adapter hooked up I can still receive signal, just a little weaker. It¡¯s so weird.?
Also when you turn the radio back on you lose tuning control. You have to reset the raduino.?
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On May 18, 2019, at 3:24 PM, Doug W < dougwilner@...> wrote: I finally got around to putting KD8CEC's outstanding FW on my V3 ?BITX.? When I'm not using the rig for other things I leave it on to rx WSPR.? Using CAT control for band hopping is fantastic.? I did not want power over the USB cable going to the raduino when the rig is otherwise switched off or at all for that matter.? There may be a more elegant solution but as they say, done is better than perfect.? I stripped back the insulation on the cable, parted the shielding, and like a B movie bomb tech I cut the red wire.? With a little heat shrink on the cut ends, some copper foil to repair the shielding, and electrical tape to replace the outer jacket it looks good as new...from 100 yards :)? I realize this isn't a revolutionary break through but I figured it was worth sharing.
--
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I read that bit about BFO adjustments till static sounded "good".? i suspect that the "good" guidance works just fine -- as soon as you ear learns what good static sounds like. hahaha.??
You also have to figure that trial and error is a totally legitimate problem solving technique in this domain. So?gird your loins and have at it. (Yes I had to look up the expression..hahah)?
I'll add to my summarization with this extra bit.?
if you want to do band hopping using the wsjt-x band hopper functions (which is wicked cool, says me), then you want an antenna contraption working on more than one frequency. My solution was my 80-10 OCFD run without an antenna tuner.? ?Yes the SWR is "variable" across the bands, but once you realize that a SWR change from 1.4 to 3.5 is small potatoes on the receiving end, you can embrace a multi-band antenna and have at it. The key here is to not actually look at SWR too often. Just run with it.?
Given that there will be a few no-go bands (no antenna seems to do it all...darn the physics), you do need to sweep your antenna as installed, find the bands with zip resonance, and be sure to EXCLUDE them from the wsjt-x band hopping click boxes.??
The dead zones for me includes 30m, where the SWR is approximately infinite. It wouldn't matter to me, but if you look at wsprnet activity reports, you see that 30m has a sizable percent of all WSPRnet activity.? See the pie charts below.? Turns out that 30m is the third most active band behind 40m then 20m then 30m.??
And my antenna is barren, lifeless, empty, massively indifferent to 30m. Think of all the action I'm missing (like in high school).? I could not let this be. So I've calculated adding? 30m OCFD wings split at 29.5% of total (to match the existing 80-10 split point). This is like a fan dipole -- and they work, right?? I expect it will completely screw up the works. I will surely? regret ever trying to improve what is really great as is. But "good enough" can always be made "worser" with enough improvements.?
So i am off to safari seeking the 30m game. Solder at the ready and push onward!
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What's a Reason for less Power Output ONLY get 4W on 80m?.., 3-4W on 40/20m, 1W on 15/12/10m
#ubitx
#ubitx-help
I need your Help, reaaly no Idea for this low, very low Power Output..
...if there is an way, an idea or something i could do it was not described in any post till now or i read it not because i have read all post for this "low output power" issue what i can read in this forum, but i find difference things was write there and i look to make all i can test or put like these post was saying.. but nothing get right..
My problem is the output transmit power, get only 4W on 80m, 3-4W on 40m/20m and 1-2W on 15m/12m/10m and the messuare was take by Dummy Load and on Antenna the Value is the same so there not different and i have on 80m only 2 Qso and 40m only 1 Qso till now with many Antenna testet and other Band testet but not heared by other ham so same by test with websdr.com try to hear me, but there was nothing able to hear me..
so the test on RV2 and RV3 with fully clockwise: Rx only is 150mA, Tx PTT only without speaking is 380-400mA?
when set on RV2 and RV3 for each on 100mA, both together 200mA to the 380-400mA then i have 600mA PTT no speaking when the Bias setting up like it should sayed on hfsignals.com but now when Tx PTT now with a load Hallooo to the original Mic Cap, then the Current is 1Ampere but on Dummy Load only 10-11V and on Power Meter 3-4W and when set RV1 to max power at fully counter clockwise then 5W getting but overmodulation so i seg RV1 like half way like it was before.. now i have test the Q90 Transistor in no Battery,no Power up Ubitx for shortet Transistor but it does not give a short with dvm test or should i test it in other way?
The Q90 was my only idea to try a new on in TO-92 solder in but i don't know if i should do this or should test other things..
The R63 resistor i have read can be reduced to 22Ohm for more mic audio.. but that should not give the issue away because on CW my power output is the same low value at the bands and on 80m get 3-4W cw on 40m 2-3W and than it goes lower,too .. on higher bands like 20m,15m,10m it was 1-2W..
What can i do, WHAT SHOULD I DO? I want only the normaly power output like on hfsignals.com saying and the other user would have..i want it too..the normaly power..this is all i want, please..
The ubix, when it have at one day should have 10w on 80m and 7w on 40m and 20m, than i would be lucky as hell but in reality the ubitx should have this 10w on 80m and 7w on 40/20m or have i fucked something up in readi g this information all there was saying by the motly ubitx users they have this minimum 10w..?
I have good Receive, very good sounding and the only thing whit trouble is the power output is too low and thats all i would be have missing would say, when this issue gone cleaned up and the power output is on the right value with 10w my ubitx would be very best Qrp Transeiver for me and i'am lucky when dreaming of this many days outdoor transmitting i would love so much with this lovley little machine.. i have so much love to give kn this ubitx and i thought for many upgrades would be present when the transmitting output issue was done in right setting, i would upgrade things like agc, s-meter, cw-filter, battery-case, speech-ic, integrated qrp tuner with swr meter, these are the things i have here for waiting to build up and put in the ubitx..
So my project only make trouble in one point where i have no idea..
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quick mod to USB cable to remove VCC for CAT control
I finally got around to putting KD8CEC's outstanding FW on my V3 ?BITX.? When I'm not using the rig for other things I leave it on to rx WSPR.? Using CAT control for band hopping is fantastic.? I did not want power over the USB cable going to the raduino when the rig is otherwise switched off or at all for that matter.? There may be a more elegant solution but as they say, done is better than perfect.? I stripped back the insulation on the cable, parted the shielding, and like a B movie bomb tech I cut the red wire.? With a little heat shrink on the cut ends, some copper foil to repair the shielding, and electrical tape to replace the outer jacket it looks good as new...from 100 yards :)? I realize this isn't a revolutionary break through but I figured it was worth sharing.
--
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---------- Forwarded message --------- From: Sandeep Lohia <sandeeplohia12@...>Date: Sat 18 May, 2019, 3:28 PM Subject: BLT To: < emrfd@...>
*C1 ground really necessary in middle?
this increasing the count of switched SM caps...
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My uBITX v3 has been sold.? Thank you all for looking.?
73, Rod WA9GQT
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Raj vu2zap
Michael Aiello
Vic WA4THR
CiccioSamui
sdr freak