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Re: Cursed?
Dave AI6K Having two uBITX boards that both do not receive well is interesting.? Normally one would be able to compare a working board with a non-working one.? Don't know what test equipment you might have available, but if just a VOM the RF can be traced from input to audio with just a home-built diode detector.? Audio can be traced with an external AF amp and speaker or a home-built AF amp (LM386...?). If you have an oscilloscope you can trace RF input all the way through the uBITX and audio out to the speaker.? Here we would be looking for presence or absence of a signal, not at the specific level at each stage.? Once you have established signal continuity you can then start looking at levels to optimize performance.? Advantage of the uBITX over other rigs is that the layout is fairly simple.? Just follow the signal paths on the schematic.? Arv? K7HKL _._ On Thu, Nov 1, 2018 at 11:49 AM David Berkompas <david.berkompas@...> wrote:
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my uBitx Power
Joe Puma
Hey guys,
I will probably have a watt meter in the coming weeks but I still haven¡¯t measured my power out on the uBitx. So with a dummy load hooked up I took some power measurements with my DMM. I am not sure if this is a good way to tell power output but here are some measurements. Voltage is 12.67 Radio idle and 12.45 while Tx¡¯ing. not sure which one matters most when calculating power or if the difference is negligible but I calculated wattage from the 12.45v band current watts 80 2.18 27.14 60 1.50 18.67 40 1.97 24.52 30 1.42 17.67 20 1.65 20.54 17 1.22 15.18 15 1.15 14.31 10 1.0 12.45 If I take into consideration the .33a for radio idle (4w) is my RF wattage 4w less then my measurements. |
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Re: Cursed?
Gordon Gibby
¿ªÔÆÌåÓýIt amazes me the problems people are having. ?I have only put one of these together, but I had absolutely no trouble. ?Used it for many WINLINK contacts. ? Before that I had a bid ex 40 which I also got to work on 80 m, and it worked fine also. ?But I remember the first rig I had as a novice, it took me six months to make it work. ?So perhaps the learning that is going on as people figure out what the problem is, which are similar to the learning that went on in my head as a high school student,
or actually useful in making better amateur radio operators out of these hams. ?
I¡¯m getting ready to help teach a general class coarse, and it has all these things about different stages in receivers and transmitters, and simple semi conductor circuits. ?Understanding the uBit ex is just slightly more complicated than what I will
be teaching the technicians going for their general class.
Gordon
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Re: Cursed?
David Berkompas
On my v4 boards, first one is latest CEC firmware (1.1), and 2nd board is stock firmware. They transmit just dandy, but useless if they can't hear anything. |
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Re: Ubitx5 ?
The question was "whether there would be a version 5 of uBITX".? Nothing to do with open or closed source for unrelated equipment from a different vendor. Arv _/_ On Thu, Nov 1, 2018 at 10:29 AM James Lynes <jmlynesjr@...> wrote:
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Re: Harmonics and Relay Replacement
The use of AXICOM relays for the LPF switching does appear to allow the uBITX to meet FCC requirements relative to harmonics based on what others have observed. The results variation relative to relay proximity to the board by as little as a "socket height" and the variation between boards is an indication of just how RF sensitive (conducted and radiated) this whole area is.?
We're still looking for a definite and measurable reason(s) for the differences and have come up with several effective solutions using a separate LPF section........ none are as inexpensive as replacing the relays. Will post pictures when done. 73 Kees K5BCQ? |
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Re: Cursed?
dear nsk, ? did you make the ubitx yourself? ?or bought? ?if bought , you had raduino, right? ?little more clarity please On Thu, Nov 1, 2018 at 8:50 PM Prathap Naidu <vu2pop@...> wrote:
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Re: Cursed?
¿ªÔÆÌåÓýSpare Radiuno is not listed on hfsignals.com But you have to send an email to hfsignals@... they will guide you to the process of buying a spare radiuno 73 de vu2pop
? From: [email protected] [mailto:[email protected]] On Behalf Of vu2nsk@... ? Sir, vu2nsk@...? |
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Re: Volume Pot
Jack Purdum
We don't actually use the onboard switch anymore. We have gone to a separate toggle switch for power, mainly because the rig then "comes up" at the last volume level. That said, our needs are likely different than most other users because we are still working on the JackAl software, so we are turning it on/off quite a bit during testing (e.g., making sure the configuration data in EEPROM are correct on startup). My guess is a simple pot and separate switch might actually be less expensive, too. FWIT. Jack, W8TEE
On Thursday, November 1, 2018, 9:26:56 AM EDT, <davesters@...> wrote:
I am using a 50k double pot without a switch on my 3 bitx radios I ganged the two halves in parallel so they are 25k.? I pulled them out of various other equipment. like old computer speakers.?
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Re: Harmonics and Relay Replacement
¿ªÔÆÌåÓýI got them from Digikey in 3 days. Had
to order something else, so shipping charges were not an issue.
On 11/1/2018 6:01 AM, iz oos wrote:
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Re: Cursed?
if stock firmware is removed, by using CEC firmware,? newer facilities like ATT and IF-S? the issue might arise, due to improper management of ATT and IF-S facilities. I suppose the reporters may have to mention the firmware and raduino used. There are others who made new? hardware and firmware too. regards sarma ?vu3zmv On Thu, Nov 1, 2018 at 4:50 PM <vu2nsk@...> wrote: Sir, |
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Re: Harmonics and Relay Replacement
I believe that the replacement with the Axicom relays should be a must in any case. I hope they will soon arrive... to make some rudimentary check... bought them on a non-sale price and still been waiting for weeks... seems like they sold them being short... Il 01/nov/2018 00:03, "Gene Nitschke" <genenitschke@...> ha scritto:
> > Sorry to ask but I been offline for a few weeks and the subject seems to have died out (after reading past posts).? So is there a final solution for the spurs/harmonics for the V3 uBitX? > > Axicom replacements (soldered directly to PWB)? > Axicom replacements with SMD inductors? > K5BCQ uBITX Relay Switched LPF/BPF board? > I have an unbuilt V3 that I am not sure if I should even complete.? I want to be legal but do not have a lot of test equipment so verification will be difficult. > > Thanks, > Gene N2IJF > > ________________________________ > From: [email protected] <[email protected]> on behalf of Raj vu2zap <rajendrakumargg@...> > Sent: Thursday, October 25, 2018 12:59 AM > To: [email protected] > > Subject: Re: [BITX20] Harmonics and Relay Replacement > ? > The before relay pic has slightly degraded performance due to the relays being mounted on > sockets. This add a few mm extra length to the leads to the contact and increases coupling! > > The second is Axicom soldered directly on PCB. > > With Axicom my boards are perfect on 40 and 80. > > Raj > > At 24-10-18, you wrote: >> >> That's pretty impressive, Raj. >> >> Jack, W8TEE >> >> On Wednesday, October 24, 2018, 1:06:11 AM EDT, Raj vu2zap <rajendrakumargg@...> wrote: >> >> >> Jim, >> >> I did? not get much improvement with Axicom in a socket.. soldering directly to board made a big difference. >> The harmonic rejection on lower bands was amazing! >> >> On one board only 20M is a bit off. >> >> Raj >> >> Example: the first is stock and 2nd is Axicom. The second needs to be referenced to -1db to compare to >> first! >> >> ? >> ? >> >> At 23-10-18, you wrote: >>> >>> No, I just used the relays.? I was looking for the simplest approach.? I have several other projects that were on hold, giving me time to try the relay swap Mike Doty originally discovered with limited but encouraging results.? >>> >>> I've done all I plan on doing regarding the harmonic reduction.? I shared what I found with the group, got unjustly accused of being a "phoney" and I now wash my hands of this part of the project. >>> >>> Back to improving the available firmware, displays and controller hardware.? >>> >>> Jim > |
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Re: Cursed?
this certainly looks like an audio problem. these challenges are often difficult to diagnose without a full signal path inspection. do you have a signal generator ? can you hook a small oscillator together for 14.318 MHz or something like that? - f On Thu, Nov 1, 2018 at 6:47 AM roger wincer <zedl2rx@...> wrote:
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YO8UFO
_Dave_ AD0B