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Re: Inexpensive eBay Amplifier Kits
Hi Joe, I would wait until you get the filters and then see what your SWR is. ?It's been a while since I've had mine on the Bird 43 looking at forward and reflected power. ?It was OK from what I remember. ?Be sure that you solder those tubes for the transformers into the supports and that the tubes are not loose. ?That may help you also if you did not already do that.
I tested the filter set on the analyzer and it looked pretty good in it's respective bands. ?I've seen better and I've definitely seen worse but they are more than usable. ?I use them with the Bitx40 and uBitx without the amp. Curt |
Re: new uBitx question
Ok, more small progress - finally received good SSB signal, approximately 300 miles away, on 80m.? Very clear.? No tones.? So it CAN work from time to time!
There's been much mention of the low audio level - but I have continuous static.? At the very lowest level (knob almost to OFF) there is static/white noise.? To increase it for "manual audio gain" - I might increase the signals I'm hearing, but it will increase the "white noise" as well, so in the end, plenty of signals are buried in my white noise.? Normal?? no? We're getting there! Thanks, everyone. |
Re: Inexpensive eBay Amplifier Kits
Right Joe, if you need many of them you end up paying more. And the ones I mentioned, rated at 300w, might not even needed for that amp. However if some have some ferrous toroids (say red, yellow or white) in the drawer buying just the mica caps may make nice filters based on a good and simple design. Il 16/mag/2019 15:51, "Joe Puma" <kd2nfc@...> ha scritto:
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Re: Inexpensive eBay Amplifier Kits
Joe Puma
¿ªÔÆÌåÓýIz, is it because the LPF is multiband while these filters you posted are mono band. If you add up all that mono band filters you will spend more on those then the eBay multiband band one. :)Joe? KD2NFC? |
Re: Inexpensive eBay Amplifier Kits
I am in the opinion that a LPF like that at 50usd is overpriced. Toroids seem small, what about the capacitors? Are these ceramic or silver-mica, rated at what voltages? You may have a look to http://www.communication-/fl1-15/,? the manuals are instructive. Il 16/mag/2019 04:09, "Joe Puma" <kd2nfc@...> ha scritto:
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Original Bitx20 design
I was going to build the Bitx20 3b but I have been mulling over the original design. Would it produce bad results to build the original design? I ask because I have most of what I'd need for that design. My intention is to build it in modules so I can experiment. That said I don't want to run afoul of best amateur practice or anything. Please let me know if it's a stupid idea. Thanks.
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Re: treble only SSB modulation
Do not use receivers that have an antenna connected. Remove the whip of the degen if possible. Transmit into a 50ohm dummy load and not to the antenna for these tests. Il 15/mag/2019 21:48, <laurent.bury@...> ha scritto:
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Re: Inexpensive eBay Amplifier Kits
Joe Puma
¿ªÔÆÌåÓýHey Curt,So I got the amp assembled but without a filter. Tests look good into a dummy load. On a antenna for just a brief keyup my turner couldn¡¯t keep the swr low at all. It kept tuning. Any thoughts? I read that blog where he mentioned a resistor change to get better swr and make the amp more stable. I¡¯m sure not having a filter is playing a role here too.? Joe Kd2nfc? On May 14, 2019, at 7:36 PM, Joe Puma via Groups.Io <kd2nfc@...> wrote:
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Re: #ubitx #ubitx-help
#ubitx
#ubitx-help
Jonathan Fritz
¿ªÔÆÌåÓýHey Curt,I¡¯m feeding the ubitx with a cheap lab bench power supply. It¡¯s intended more for electronics hobbyists than for ham radio, so it¡¯s entirely possible that it is not a clean power source.? Unfortunately, I don¡¯t have a scope with which to confirm this theory. I¡¯ll ask around my local club and see if I can either borrow a scope or another low wattage HF unit with which to try the PS.? In the mean time, I¡¯ve managed to upgrade the firmware on the ubitx and will go through the calibration routine that you recommended, and then report back.? ¡ª Jonathan Fritz VA3 JFZ? On May 15, 2019, at 2:32 PM, Curt via Groups.Io <wb8yyy@...> wrote:
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So once again I made some progress. I have not located the exact cause of the end of the transmission yet, but I am sure the problem lies within the fake AM mode of the uBITX: |
Re: treble only SSB modulation
Hi!
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I highly recommend doing it using a sound card microphone input. That way you can adjust the passband using something like fldigi to monitor the noise floor in the passband. -adrian On Wed, 15 May 2019 at 12:48, <laurent.bury@...> wrote:
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Re: treble only SSB modulation
Hello, And yes, I was surprised at first by the too higly pitched received modulation: it is a good second facts that leads to a BFO calibration problem. |
Re: #ubitx #ubitx-help
#ubitx
#ubitx-help
Jon
maybe I should have asked what kind of power supply you are using -- a battery or something 'intended' for ham radio use?? a PC type power supply might garble things pretty well (it depends).? the ubitx gets its local oscillator from a crystal source, being a very nice (but inexpensive) PLL.? about the only way to easily mess it up is to feed it cruddy power.? while its possible it is less likely that something on the board has gone bad.? if one or more capacitors were damaged enough to completely break them) - something could be distorted.? but I would expect obvious physical damage.? CW is harder to distort with a bad BFO setting - if you can hear it there should be a place to tune it in - unless BFO is so far off that it is coming in way down the skirt of the crystal filter.? okay if you power supply is clean (such as other rigs are happy with it) - then I would investigate your BFO setting.? Curt |
Re: Inexpensive eBay Amplifier Kits
I got the single chip 80w/100w (depending on voltage) version on Aliexpress. NO instructions whatsoever, it differed slightly from the pics in the listing, the chip was not new.. Aside from that, it works fine. Plenty of stuff on the web detailing builds of these style boards, so You can average them all out and get the build done without making a splatterbox if You use Your head. Mine had much of the construction already done - i think they build the boards up to a stage where they can have components added to the bag depending on what version has been ordered. You can see how it will support a pair of transistors in PP, or the single ceramic i got etc.
Works well enough with ft817 and uBitx, when driven gently for digital modes using the on-board loop for a LPF. It's response to drive is not in any way linear, it appears to be not working, then takes off when You pass a threshold, so if You are testing one, jack up the drive very slowly. Mine was advertised at the time as working on 6m, i found this was not the case. Keeping things in the spirit of the uBitx, this is a good addition IMHO, just be prepared to suck up any lack of support or gaps in reality, and have a plan about a filter for this version, as this is clearly going to make You very unpopular without one. |
Re: treble only SSB modulation
it is your BFO calibration.? There is a you tube to watch 73 kd5yyk
On Tuesday, May 14, 2019, 3:41:10 PM CDT, <laurent.bury@...> wrote:
Hi there uBitx owners, For information, I just use the electret mike as delivered with my V3 board. |
Hi,
Good things come to procrastinators... This KV4QB site has a lot of interesting Ham related microprocessor projects. Including adding a TFT display to a uBitx. And a cool simulated analog meter using a small OLED display.? He has a project for a 63 db step attenuator using eBay attenuator modules. I recently bought two to do the same thing. And when that day comes I have some spare time I was going to hash together some kind of Arduino code to control them. Right there on his site is code to do just that. Maybe if I stay busy with client projects, my soldering iron will build the thing for me (Maybe like Disney's Fantasia. Although I seem to remember things went terribly wrong when inanimate objects were set off to do work). Well, maybe, procrastination won't be rewarded at that level. Tom, wb6b |
Re: Look at this on eBay, ubitx, budget test equipment.
I bought one of these signal generators (FY6600) about a year ago. It can do everything I require for HF and is accurate enough for my needs. It has a lot more functions than I expect I will ever use seriously. it is quite entertaining playing around with it? though if you have a scope available.? I am a? bit on the careless side (see bin of dead Arduino nano's by my bench) and have not managed to damage it yet.? On the not so good side the screen is a bit small but the PC application that you can download for it solves that. A couple of locks ups requiring a re-start and thats about it. Cant go far wrong at the price I think.?
Jim |
Re: treble only SSB modulation
You may like to hear your modulation yourself with another receiver. You transmit into a dummy load and you receive without any antenna. I have ver. 3 and has no basses, say lower than 500hz. Listening to my SDR receiver I like my modulation a lot! Excellent for dx. I had generally excellent reports. However I trust more of what I hear myself than the reports by others. Not always their carrier is yours, they might have strange settings in filters, pbt etc Il 14/mag/2019 22:41, <laurent.bury@...> ha scritto:
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