Date   
Re: wsprnet results, wsjt-x, and calibration success --> world domination V4 #calibration #firmware

Don - KM4UDX
 

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!

Re: quick mod to USB cable to remove VCC for CAT control

Joe Puma
 

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. 



Joe
Kd2nfc 



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 µBITX.  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.
--
www.bitxmap.com

Re: Lista component for ubitx 5 #ubitx

CiccioSamui
 

Thanks exactly what I looking for...... 

Re: wsprnet results, wsjt-x, and calibration success --> world domination V4 #calibration #firmware

masch57
 

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.  

Re: Homebrew li-ion battery pack into ubitx

Sandeep Lohia
 



On Mon 15 Apr, 2019, 8:42 PM Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> 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:
    https://www.mikeselectronicparts.com/product/variable-capacitor-335pf-20pf/

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:
    https://www.qrpkits.com/sota.html
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...

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

Curt
 

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

Re: uBitx "Shadow"

 

V4: One you do the spur mods these should reduce or go away!

Raj

At 18/05/2019, you wrote:
Thanks for your advice, Evan./// It's model V4. Thanks!

Re: Inexpensive eBay Amplifier Kits

MVS Sarma
 

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

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

Vic WA4THR
 

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=

Re: uBitx low signals on the speaker

jfein2000@...
 

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
 

 

 

Re: µBITX V5 build complete (for now)

Balasubramanyan Cp
 

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.

On Sun, May 12, 2019 at 3:35 AM Jeff Karpinski (N0KAI) <jeff.karpinski@...> wrote:
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 (https://www.circuitspecialists.com/metal-instrument-enclosure-la-6.html)

Re: Homebrew li-ion battery pack into ubitx

Balasubramanyan Cp
 

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 Sun, May 19, 2019 at 1:13 AM Sandeep Lohia <sandeeplohia12@...> wrote:


On Mon 15 Apr, 2019, 8:42 PM Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> 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:
    https://www.mikeselectronicparts.com/product/variable-capacitor-335pf-20pf/

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:
    https://www.qrpkits.com/sota.html
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...

Re: Antuino

Michael Aiello
 

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

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

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

Re: Antuino

Ashhar Farhan
 

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

On Sun 19 May, 2019, 7:39 AM Michael Aiello, <n2htt.mike@...> wrote:
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

Re: wsprnet results, wsjt-x, and calibration success --> world domination V4 #calibration #firmware

Don - KM4UDX
 

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)

https://myantennas.com/wp/product/efhw-8010/

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. 

Re: Homebrew li-ion battery pack into ubitx

Jerry Gaffke
 

Sandeep wrote:
> Guys, any way can we know voltages approx across 20M traps ?
> excited with 25 watt...

I'll assume you have a 40m dipole, with 20m traps halfway down each leg 
to prevent 20m energy from passing, so it is effectively a shorter dipole on 20m.

When operating on 20m, those traps are at the ends of the 20m dipole,
those ends have the same 3000 ohm impedance that we would have at 
the feedpoint of an end fed halfwave.  Actual impedance will vary depending on
trap construction, how close the wires are cut for resonance, nearby objects, 
height from ground, ...    But I'd expect this to be correct within a factor of two.

Power is Volts*Amps, or Volts*(Volts/Ohms).
25watts = Volts * Volts / 3000ohms,   so Volts = square_root(25 * 3000) = 274 Volts rms of 20m RF

Jerry, KE7ER



On Sat, May 18, 2019 at 03:13 PM, Sandeep Lohia wrote:
On Mon 15 Apr, 2019, 8:42 PM Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> 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...
 

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

sdr freak
 

Hello and thank you HAMs!!

This is the Ubitx of mine:


How exactly is this meant by the audio oscillator, a 2 tone generator? I don't have one yet.
Use only the original mic cap and a zetagi m99 as second mic for testing, both have the same output power. 
 
Measure the CW power? How can there be differences, how is that meant? 
The CW Key is an older model which I had on the Kennwood TS140s, so I always set the SWR for antennas. Tuner is the MFJ 948 Versa II with SWR and Watt Power Meter. 
 
The 10-11V which I read 80M in the dummy load I measure with the DVM in position DC, dummy load DL1 QRP replica of the Elecraft DL1... and my input in the Ubitx is the same at 12V on the red and brown cable. Even at 12.5V input power there is hardly any difference. The 10-11V at 80m and at 40m there are only 8-10V at the dummy load.
 
I just wanted to say I use the Ubitx 3 with FCI Sound IC and have connected a 20x4 display and installed the software from CEC 1.08. Use indoor a 12V 3A power supply(can handle up to 15V but i don't do more than 12V or maximum 12,5V for the Ubitx) and outdoor a 12V 3Ah battery from motorcycle.
 
Indoors I test with dummy load, replicated from the Elecraft DL1 QRP 20W dummy load schematic with the same components and outdoors with 80m dipole, 40m dipole, 20m delta loop, 15m dipole, 10m yagi, 40m groundplane with loaded coil and another 20m groundplan worth of 1/4 wave lenght.

With 40M Groundplane with loaded and 3 radials, i have an little qso from Germany to France last Week but with 3-4 watts.. but this was the only Qso able to make because many other try but with no copy, and i look for hear me at websdr.com in half europe i select stations and try to hear me in ssb and cw, but nothing was heared, not even a cw signal heared from my self..
 
What is meant by measuring CW? Measure the power of CW when Ubitx is on a frequency for it and with a normal Morse key. Then I read the power on the wattmeter and so I should be able to see what the right result is or how should I do it, is there an error in my method or is 4-5W on 80M and 2-3W on 40M and 20M on CW normal? 
 
I have the homebrew Mic with the standart delivered Mic Cap which was in the Ubitx Box und my second Mic is a Zetagi M99 with Hall function, but on both mic the output is same.. Even many other Mic Cap i have tested with same or lower Output..
 
The main question now is which part of the Ubitx should I check and are there data for the voltage or current values of the parts to be tested which correspond to the correct value? 
 
I have the idea to minimize the R63 to 22Ohm to not have to scream so close in mic to get any performance out of it, because it's really bad if I don't eat the mic very close to my mouth.
 
I had an idea to replace the Q90 transistor with a TO-92 type 2N3904 transistor and hope for an improvement of the higher watt output power. But should I do that even if the Q90 doesn't have a short circuit?
 
If I open the RV1 completely I don't have much more power than before with half to 2/3 counterclockwise. Only from 4W on, if at all, 5W are there to measure at 80M is the increase at full counterclockwise.
 
I was able to measure from 1.2A(4W) to 1.8A(5W) at this RV1 test with PTT with loud hello.
Then I tested if the other transistors in the amplifier stage have a short-circuit, but also here none was to be found, all tested in the switched off state as well as in Q90 test for short-circuit... 
 
Or should I test this for short circuits of the transistors in switched on state with device in Rx or in Tx mode?
 
What cause can it still have that instead of the normal power of the 10W like hfsignals.com also writes on their page, and also here the users except for a few who had there also problems but with other cause, only this few watts with my ubitx comes out although I have no other problems with the reception and use the 12V power supply with 3A as recommended?
 
What exactly could I do now, what exactly should I measure for you or could a video of something help, then I would do it, I just need to know what I should show then I do it immediately.
 
I want to make it somehow but I need your help, I am so thankful for every help!

Re: treble only SSB modulation

laurent.bury@...
 

Hi,

well I finally hooked up my headphones output to FlDigi, and that confirmed my uBitx's BFO was off, giving an audio about 300Hz too high, which I corrected successflully via the setting BFO menu (I guess my problem was different with Vaughn's one).

I will try to make some phone contact to confirm the transmit audio is actually better now, as I don't have a dummy load to avoid overloading my test receiver.

Thank's again to all of you for you great help.

73s.


--
Laurent F5FIE.

Re: Homebrew li-ion battery pack into ubitx

Cor Beijersbergen
 

Please, what is the relation of the subject line with the contents of this message?

Cor – PA4Q

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Sandeep Lohia
Sent: Sunday, 19 May 2019 00:14
To: BITX20@groups.io
Subject: Re: [BITX20] Homebrew li-ion battery pack into ubitx

 

 

On Mon 15 Apr, 2019, 8:42 PM Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> 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:
    https://www.mikeselectronicparts.com/product/variable-capacitor-335pf-20pf/

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:
    https://www.qrpkits.com/sota.html
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...