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Re: uBITX Tx timeout
¿ªÔÆÌåÓýActually it is fairly easy to modify
the Raduino code to put a timer in it to turn off the xmit after
some time.
On 10/31/2018 1:18 PM, Bill Cromwell wrote: Hi Dave,
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Cursed?
Woody
Original thread was "RX Trouble". ? Sort of a rant here...
I am not superstitious but beginning to believe my uBITX (both factory & CEC firmware) is cursed. Have had issues since first power-up, but now I think the problems are fatal.? Have a lot of time & money in it (Axicom relays, trouble shooting, etc.) but think I might call it quits.? Never had problems with my scratch built rigs.? Had a problem with my K2 build, but fixed that when I discovered a copper whisker (under the coating, I took optical micrographs !) shorting a pair of runs on the control board. However, the uBITX has been a relative nightmare. Original issues, to name a few: Not on frequency, low audio, poor RF sensitivity, pinched audio response (narrow - filter issue?),? very narrow tuning for understandable audio, etc. I fixed the too low for headphones audio with an off board amplifier.? But, the distortion was even worse from the speaker. I found a power/signal driven oscillation in the external amp and fixed that.? Afterward, the volume was OK and the distortion was somewhat lower - but still not great audio.? The other problems remained. Observation: There was (I think, maybe) something oscillating on the board. There was a low level (~700) Hz tone on the audio coming from the board.? Found that with a 'scope, but did not find the source. Also, the 12 MHz crystal filter was rather microphonic - With no received signals lightly tapping crystals produced audio output. Normal?? Not normal? The TX power was inconsistent with measurements by others.? Got 10 +- watts out on higher bands, dropping a bit as frequency increased.? But, for 40M and below, the power dropped to about 1.5 watts while the supply current was much higher (almost by 1 amp). ? Frustrated with the RX problems, decided to look at the TX power issue using 'scope on TPs in the TX amp stages. -- The following is when the patient died. No brain activity ;) -- CW keyed the TX for testing but I didn't get far before the fatal problem occurred. After a few short dummy load TX sessions, it stopped keying.?? Immediately noticed a display issue.? The top row was all solid fill characters, nothing on the bottom row. Clocks 0, 1, 2 not there.? The 7805 on the Radiuno is supplying 5 v.? This is a bit subjective, but is does not seem to get quite as hot as initially? -? likely not supplying as much current as before?. Hoping the cause was somehow corrupt firmware, tried reloading. Xloader appeared to connect and tried to upload, but never left the "uploading" mode - Failed to reload firmware.? The display stayed the same - solid top row, empty bottom row. Tried uBITX Manager to read.? It appeared to connect, but when "Read from uBITX" was attempted, returned this:? "[8:30 PM] Error Receive Length = 0/1027". OTOH,? uBITX Manager did report success when told to upload the .btx backup file I created earlier (Load from File).? BUT - it again failed the "Read from uBITX" command.? Display never changed.? I get the impression the Arduino died... Ready to take it outside and shoot it? ;) , but probably will put this project away for now.? A big question is, if a version 5 is released to fix some of the original issues like spur/harmonic levels, do I try again ???????? Better luck to everyone else! 73,? Woody?? KZ4AK |
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Re: Dummy Load Resistors
John Lauber
?I ordered far too many of the 1K/3W resistors for this project.? I've enough of the passive components plus D1(BAV21) for four additional builds.? ?I've made up four kits consisting of 20 1K/3W, 1 56k, 2 1k (don't have 2k in my box)? resistors, D1 and C1 (50V--ok for QRP, but if you want the 150W version you should replace with a 250-500V as specified).? Drop me a private email if interested.?
John WI6P |
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Re: CW key in LSB mode?
Moving the BFO to the other side of the 12mhz crystal filter can make a difference,
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as the skirts of the filter are shaped differently. Also, moving the VFO to the high side (on the Bitx40) or clk1 to the high side (on the uBitx) can have considerable impact on the birdies that the receiver sees. Dangerous to make any blanket statements here as to what works best. The uBitx is quite different from the Bitx40. The various firmware releases can do different things. What is best can also depend on what characteristics you are looking for. Jerry, KE7ER On Wed, Oct 31, 2018 at 12:20 PM, roger wincer wrote:
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Re: CW key in LSB mode?
Ty,
make sure semiQSK is ON in the SETTINGS menu. If the radio is in LSB mode, it will switch to CW automatically as soon as you push the CW key. (if it's in USB it will switch to CWU). Press PTT to go back to LSB (or USB). However when semiQSK is OFF, you need to select CWL (or CWU) manually and press PTT manually for transmitting CW. 73 Allard PE1NWL |
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CW key in LSB mode?
Hi all,
I've had my bitx40 working for a few weeks and now have implemented the??amunters/bitx40? goodies. Thank you developers and testers! I was surprised that nothing happened with I pushed the CW key in LSB mode... nothing happened. I expected it to switch to transmit CW on an appropriate CW offset then switch back to LSB receive. Is that not workingon my board or is it not a feature? I didn't find it looking in the code but I thought I ask more experienced operators and code gurus before I dug deeper. TY, Ed - aa2mz |
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Re: Sideband rejection
Am 30.10.2018 um 06:43 schrieb Raj vu2zap:
Set the BFO to 11.9965 and see if that works.Thanks Raj ! Had again to correct the calibration which was exactly 1 kHz off. After playing a while with Sunils calibration method I got it calibrated on 10,000.000 and then played with the BFO. Tested all BFO values from 11.995.0 to 11.996.5 The best result I got at 11,995.3 with -28 dB sideband rejection both on USB, LSB, full carrier rejection and nearly equal and good sound qualitiy on USB and LSB. The bandwidth was about 3 kHz. 73 Matthias, DD7NT |
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Re: uBITX Tx timeout
Hi Dave,
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Obviously unattended operation is allowed where you live and are licensed. Some of that is allowed where I live too but the problem you have outlined is the main reason I don't do unattended operation. The remote controlled power switch that Kevin suggests looks like a good solution but you will still have to know when it needs to be used. Good luck with it. 73, Bill KU8H On 10/31/2018 02:25 AM, David - CA3DPV wrote:
Hi, --
bark less - wag more |
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Re: uBITX Tx timeout
Get a smart outlet (something that you can control with Echo for example) and shut the outlet off if you have a problem Kevin? K5KDT On Wed, Oct 31, 2018 at 1:25 AM David - CA3DPV <david.parra@...> wrote: Hi, |
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Re: Buy in INDIA
Hi Timothy http://www.hfsignals.com/index.php/2017/11/23/bitx40-circuit-description/ - C103 , 3 pads between xtal and T4 on the PCB for the trimmer. If those boards were an early batch (or you have modified) the diodes (2 with balance pot?) could well be mismatched. Replacing both should bring balance within the pot's ability, particularly if you measure them with an ohmmeter / DMM. Later versions had the ready-matched pair-in-one-package. You might find fragments of the diagram with specific modifications, but that one above is the 'master'. Past messages in the Group give the info, as detailed on hfsignals site 'help'. Farhan has contributed here, researching his input would give the info 'from the horse's mouth' (as it were). development is ongoing in the Group, mainly for the uBitx but bits are applicable. Above all, READ. It's all in English (as here too), so our Spanish friends may encounter difficulties there - but if successful I'd encourage a translated site (a lot of other 'Latino' Hams would appreciate it!). From hfsinals website: |
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Re: Need 12.000 MHz crystals for the BITX40
#bitx40help
#bitx40
¿ªÔÆÌåÓýAnd, of course, the Elecraft K2¡ ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Jim Sky
Sent: Tuesday, October 30, 2018 5:48 PM To: [email protected] Subject: Re: [BITX20] Need 12.000 MHz crystals for the BITX40 #bitx40 #bitx40help ? This is the same method used in the Ten Tec Rebel. The Rebel circuit also uses voltage controlled coupling at the ends of the ladder filter.? It provides 3 distinct and surprisingly effective bandwidths using only 3 IF crystals. I have wondered if it might be used in the uBitx or Bitx 40 but have not tried it. On 10/28/2018 5:44 PM, MadRadioModder wrote:
? -- ¡_. _._ |
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uBITX Tx timeout
Hi,
I use an old laptop for FT8 with my uBitx and works perfect (CAT via USB). But sometimes my computer hangs (BSOD) and, when the uBitx is in Tx, the radio keep transmitting. I use this computer via TeamViewer, but i don't wanna fry the power output when i'm at work and i can't power off the radio when my PC hangs. Can i set a TOT to protect my radio? Any firmware with this feature? 73 from Santiago de Chile, David, CA3DPV |
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Re: Buy in INDIA
Timothy Fidler
DM - had to send reply this way as you have rigorous? Spam filtering on and private email was REJ . If you could tell me "the appropriate place? " where this trimmer should be put? (Well documented - as per a? piece of instruction arriving with the kit maybe ??) I will forward it on to him.
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he is about to bundle the Bitx40? kit as Repaired by Him? so it can receive and sent it back to the buyer in Spain and tell the original buyer (of a whole set of them)? what he is working on is mostly? a crock.? He is fed? up with spending time. on it as it was a? mess in terms of performance as it came out of box. I have seen his wiring photos and it all looks nicely done and heat shrunk.? He was using the screen of? a KX3 as a spectrum analyser to diagnose things. so he is not some plumber trying to do RF wiring .? How can anyone solve problems if the on the web schematic is not up do date on this diode change out bizzo ?? ?Perhaps it is.. perhaps there are Multiple master schematics floating around ?? "you get that on the Cloud." ?
If you forward technical insights with specific URLs,? I will forward them.??
?
It is possible that the diode pair he has is defective or that it is a mixture of? silicon and schottky.? Such assymetric pairs? are made for use as PIN diodes;? what is to stop them getting onto the assly line in Mumbai. ?? All the evidence is that the diodes are being over powered in TX ;? it now works in RX ie at low diode forward current? with a MAJOR user rework.? ?since the diodes? were feeding into a CT 500R load with Pi downstream before the change? .. Do you know what changes were made on the Tx? amp section prior to BM section to ensure? diodes stayed in? ?A exp (I)? ? functional range - which is required for a diode based modulator to work ??
?
Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 CB #2885,? ?
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Re: Mike element
Labtec makes a good computer mic that does a good job on the ubitx. I have 2 of them. Also, I had a avalier mic that I bought sometime back from China for $1.99. It works good though not quite the output of the lab tech. Another alternative is to use a mic pre amp. John, vk2Eta did that and wrote it up on the HHSignals site. Those pre amps are cheap. He integrated it to the uBitx. You could make it a stand-alone power mic, like d-104 or Turner SuperSidekick only with electret element instead of dynamic.?
If the obstacle in front of you is too high to jump, dig a tunnel or go around.. -- 72 and God bless KD4EPG |
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Re: Need 12.000 MHz crystals for the BITX40
#bitx40help
#bitx40
¿ªÔÆÌåÓýThis is the same method used in the Ten Tec Rebel. The Rebel circuit also uses voltage controlled coupling at the ends of the ladder filter.? It provides 3 distinct and surprisingly effective bandwidths using only 3 IF crystals. I have wondered if it might be used in the uBitx or Bitx 40 but have not tried it.Jim KH6SKY On 10/28/2018 5:44 PM, MadRadioModder
wrote:
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Re: uBitX CW Sidetone Volume
Marko Pavlicevic
Disconnected main pot and applied CW TONE direct to amplifier (R253 direct to VOL-M).
Now, CW tone can be lowered (with pot across C252) and there is no bumping sound. So, when TX is off, and you remove R253 from the circuit, you can still somehow hear CW tone, that comes from Q70. How is that possible? |
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Re: New file uploaded to [email protected] + CW Keying
Checkout www.w0eb.com
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On October 30, 2018 at 1:11 PM barry halterman <kthreebo@...> wrote: |