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Re: BITX QSO Afternoon/Night, Sunday, February 25, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Vince Vielhaber
You still on 3977?
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Vince. On 02/25/2018 07:31 PM, N8DAH wrote:
just not a good night I guess --
Michigan VHF Corp. |
Erratic tuning with my new uBitx
My new uBitx is up and running on receive (it also transmits but I haven't wired the mike yet). ?However, tuning is very erratic. ?Sometimes while tuning it suddenly makes large frequency jumps. ?Other times, I can turn the encoder and the frequency doesn't change. ?I"ve tried poking at connections etc, looking for something lose, but nothing shows up. ?Could I have a bad encoder? ?
Thanks Howard K4LXY |
Re: Broadcast band interference, uBitx
Thanks for all these suggestions. ?Mysteriously, the problem has disappeared. ?However, it may be that the station is off the air. ?I see what happens tomorrow. ?One note: ?I did not have the problem with the antenna disconnected.
If the problem comes back, I'll start with your suggestions. 73 Howard K4LXY |
Re: BITX QSO Afternoon/Night, Sunday, February 25, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Vince Vielhaber
I'm on 3977, not hearing ya.
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Vince - KA8CSH. On 02/25/2018 07:24 PM, N8DAH wrote:
Tried 7.277 a few times qrp and at about 30W nothing heard going to call --
Michigan VHF Corp. |
Re: Escaping smoke
#ubitx
I did some post-mortem examination on the audio output stage today after U1 and R75 went up in smoke.? Here is what I found: As Jerry pointed out above, plugging in a mono jack to the ¡®phones¡¯ jack will short the output to ground.? I believe that this is exactly what I did.? I tried to plug in an extension speaker with a mono jack I¡¯m pretty sure that that is when the failure happened. ?I was able to carefully remove U1 and there appears to be no damage to the board or any traces.? I also removed what was left of R75 and cleaned up the board with alcohol.? Interestingly, a pad on one side of R75 appeared to have little or no solder. This was the side of R75 attached to pin 6 of U1 (input 2 +). ? ?I carefully applied power to the unit ¨C all seems well except no audio output of course.? Transmit on SSB and CW are working.? I could hear a modulated SSB signal on another receiver which sounded OK.? I probed the connection to U1 pin 7 (input 1 +) with an oscilloscope and was able to see a signal.? I then tuned the rig to 14.074 (20 meter FT8) and sure enough, every 15 seconds the signal would briefly disappear and then reappear for another 15 seconds.? This indicates to me that the previous audio stage is working ¨C here¡¯s hoping anyway.? I thought about injecting this into an external audio amp but decided not to push my luck ¨C I¡¯m just going to wait for the parts to arrive and work on a case in the meantime. ? Did not mean to ramble so much, but decided to post this in case it might help someone else. Incidentally, I probably qualify as an old timer ¨C first licensed in 1960.? Still learning something every day and making rookie mistakes! ? Bill ? ? |
Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
Vince Vielhaber
According to my cheap wattmeter (that I know reads low) I'm putting about 120 watts into a 135' wire (and 9:1 balun) at 15'. That same electric fence wire I mentioned. Yes, 15 feet above ground - I recently measured it for those wondering about my previous comments on it. With a cheap MFJ tuner I've worked 160 and 75 regularly. Without a tuner used it on 40 with my B40 and worked a bunch of digital and I have a flat SWR on all of 20 meters.
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Currently I'm using a cobra antenna (not the CB radio cobra, it's named after it's style, google it, easy to make) at 40' sloping down to about 10-15'. With a tuner I get a near flat SWR on all bands 160-10. Vince. On 02/25/2018 06:59 PM, Mark via Groups.Io wrote:
Hi Vince, --
Michigan VHF Corp. |
Re: BITX QSO Afternoon/Night, Sunday, February 25, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Vince Vielhaber
I'm here right now, S1 noise level, not hearing anyone.
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Vince - KA8CSH. On 02/25/2018 06:48 PM, at91r40008 wrote:
Don't here anybody. I called but no taker. --
Michigan VHF Corp. |
Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
Hi Vince,
For QRP I'd only need #17? There's a write-up on this type of wire purchased from tractor supply stores, entitled, Does wire gauge (size) make any difference for vertical antenna radials?, at eHam.net. They say that some antenna manufactures suggest 14. I guess that is possibly because it is used for base stations with 100 or more watts. However, for my specific QRP & mobile situation, maybe 17 would be fine. It would also be a bit lighter. Would reception improve if it were copper? Or, maybe for something like this it wouldn't really matter. Thanks, Mark |
Re: Strong carrier on transmit.
#bitx40help
Hi Dale, I disconnected D20 from the input of the attenuation pad going into the tx amp and the carrier was reduced but still there. I was wondering if the 12 MHz oscillator output could be leaking into the tx amp. I also get a large burst of of RF when the ptt is pressed. I read in earlier posts that they never found a solution to the ptt RF burst problem. I also read that with the diodes and the pot that it was normal to get a 1vpp output at the antenna with no audio input. Would you mind you mind discussing this problem on the land line.? Thank You Bob WB2TFG ex
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Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
Thank you Mike,
I am going to be copying these instructions (along with lots of other comments) into my amateur radio notes text file. I didn't realize I'd get this much of a response! It's like having a custom-designed lesson. I don't take it for granted. There are YouTube instructions on this that I'll combine with your instructions. Making an antenna doesn't seem that difficult. A few basic tools. The most expensive one (that would be worth the investment) may be an SWR or antenna tuner. Appreciate it, Mark |
Re: Raduino Replacemnt, COMING SOON!
Ok, Well, thanks for spotting this error. Lucky I only have 20 of these boards on the first order...
Easy enough fix as per Jerry's post. I suggect just replacing the last 3 headers with the 104 caps with their legs bent in opposite directions, as cutting the tracks will be difficult, they are only 0.5mm... I have fixed up the Rev.01 board for the next run, I have had to remove one of the mounting holes for the Si5351, but thats OK, I was only going to mount it with the header pins anyway... 1206 SMD should work fine on those TH pads if you choose to do that also... TOP: BOTTOM: 73, VK4PLN |
Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
Jerry,
I think I understand what you're saying. If I had a multiband transceiver, & wanted to make my own dipole, then I could keep it simple at first by justing making one for the longest wavelength (40) meter. The, if that works, add some gadgetry for isolating a portion of the dipole (traps)? That kit dual-band kit from Pacific Antennas that Dave was talking about is cheap enough, only $25. According to the PDF it seems rather easy to put together with minimal tools. Except I might need an SWR. Plenty of options! Mark |
Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
David,
I appreciate the suggestion. It seems I have much studying to do before I decide what I'm going to do for an antenna. Making my own seems to be a reasonable idea. From what I've seen so far, it can be done with simple tools. Plus it would be nice to know how to put one together with a roll of wire, just in case. Peter Parker says fences, railings, & even bridges can be used! Mark |
Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
Vince Vielhaber
Go to tractor supply and pick up a spool of galvanized electric fence wire, 17ga. You get a 1/4 mile spool for under $20. You can also get 4" spacers to make your own feedline and a whole host of other things.
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Vince. On 02/25/2018 12:48 PM, Michael Hagen wrote:
A good source of wire for a dipole is to buy a 250 roll of #14 Stranded --
Michigan VHF Corp. |
Re: Looking for Completely Functional Dual-Band 20/(17/15/10/6) Meter QRP Rig with SSB/PSK
#bitx20help
Hi Rich,
Thanks for the suggestion. Yes, I've heard that before. They don't necessarily need to be clipped. They can just be bent? More information for my antenna book. Great! Mark |