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Re: Antuino now available for purchase
It is a fully tested unit in the all metal case. It has an internal battery case for 6 AA cells. Two SMA connectors. On Mon 12 Aug, 2019, 5:00 PM Mike Short, <ai4ns.mike.spam@...> wrote: Does it come with the case? |
Re: AGC Circuit for uBITX Featured in July 2019 QST Magazine
Ian Reeve
¿ªÔÆÌåÓýThe voltage rating on the capacitor is the maximum the component can ¡°deal with¡±. It works absolutely fine at lower voltages of course and it is best to give some headroom for example on a 12v rail,use 16v capacitors. There is no problem going up to say 25 or higher voltage rating,just expect a physically larger component which might not fit in the desired space. Electrolytics are happiest when run at 50%? and above of their stated voltage, they tend to deteriorate if say a 100v component is used on a 12v rail. The low voltage in comparison to their rating does not properly keep the component and its chemicals in proper balance. ? This is why equipment not used for some considerable time needs careful powering up because of the deterioration of electrolytics deprived of polarising voltage. ? For a 12v DC ?rail use 16v or 25v components. ? Hope this helps ? Ian M0IDR ? Sent from for Windows 10 ? From: [email protected] <[email protected]> on behalf of David Wilcox via Groups.Io <Djwilcox01@...>
Sent: Monday, August 12, 2019 11:21:17 AM To: [email protected] <[email protected]> Subject: Re: [BITX20] AGC Circuit for uBITX Featured in July 2019 QST Magazine ?
Can someone explain the reasons for certain voltages listed on any schematic for the electrolytic caps, AND what problems could arise if one used a cap with a larger voltage rating? How much higher a voltage cap could be substituted without causing a problem?
Dave K8WPE?
David J. Wilcox K8WPE¡¯s iPad
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Re: AGC Circuit for uBITX Featured in July 2019 QST Magazine
David Wilcox
¿ªÔÆÌåÓýCan someone explain the reasons for certain voltages listed on any schematic for the electrolytic caps, AND what problems could arise if one used a cap with a larger voltage rating? How much higher a voltage cap could be substituted without causing a problem?Dave K8WPE? David J. Wilcox K8WPE¡¯s iPad On Aug 12, 2019, at 2:18 AM, MadRadioModder <madradiomodder@...> wrote:
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Re: Antuino now available for purchase
Can you guys wait for me to say it?? (Grin) On Mon 12 Aug, 2019, 2:22 PM Jim, <Jscook@...> wrote: Good news. Everyone has been waiting. Thank you. |
Re: AGC Circuit for uBITX Featured in July 2019 QST Magazine
¿ªÔÆÌåÓýSince the entire circuit set is 12V or less, your 16V caps should work just fine. ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Rob French (KC4UPR) ? Thanks.? Any thoughts on voltage rating for the capacitors, especially the "big" electrolytic ones?? (10uF, 100uF, 470uF... I'm assuming they're electrolytics.)? I looked at the Hycas schematic, and that calls out 50v for all the caps, but I don't have many of those... got lots of 16v though! -- ¡_. _._ |
Re: AGC Circuit for uBITX Featured in July 2019 QST Magazine
Thanks.? Any thoughts on voltage rating for the capacitors, especially the "big" electrolytic ones?? (10uF, 100uF, 470uF... I'm assuming they're electrolytics.)? I looked at the Hycas schematic, and that calls out 50v for all the caps, but I don't have many of those... got lots of 16v though!
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Re: AGC Circuit for uBITX Featured in July 2019 QST Magazine
¿ªÔÆÌåÓýAs I recall, the JackAl AGC circuit is just the Hycas AGC circuit lifted from QST December 2007.? Al added a couple of things like a switch to turn it off.? The FETs are nothing special.? A 201 and a 102 will work fine. ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Rob French (KC4UPR) ? I'm looking at possibly lifting just the AGC circuit out of the JackAl design, and seeing if I can stock it out of my junk box.? But... the only JFET's I have are MPF102, J201, 2N5486, and 2N4393... will any of those work?? Other than the MPF102, the rest were all originally purchased for audio work, so I can totally imagine them not being suitable. -- ¡_. _._ |
Re: AGC Circuit for uBITX Featured in July 2019 QST Magazine
I'm looking at possibly lifting just the AGC circuit out of the JackAl design, and seeing if I can stock it out of my junk box.? But... the only JFET's I have are MPF102, J201, 2N5486, and 2N4393... will any of those work?? Other than the MPF102, the rest were all originally purchased for audio work, so I can totally imagine them not being suitable.
Thanks! -Rob |
Re: Calibration success
#ubitx
#calibration
For transmitting CW, clk2 drives mixer d1/d2 at the transmit frequency.? The modulator, 2 crystal filters, and 2 IF amps are not used.? When transmitting SSB, all of that stuff must work. Jerry, KE7ER On Sun, Aug 11, 2019 at 08:56 AM, Evan Hand wrote: Dan's suggestion on CW as a test is the correct course.? It will verify if you have an RF or Audio issue. |
Re: uBitx and QCX review in QST August 2019
Asher, You may wish to contact ARRL and ask permission to host a PDF of the review article on your own website.? I'm not sure what the arrangement is for that sort of thing, but I've encountered that several times.? For instance, Elecraft has PDFs of the various ARRL review articles of their equipment for free download on their site. 73, -- Dave, N8SBE
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Re: Calibration success
#ubitx
#calibration
Thanks Dan!
I appreciate the response. I did lookup the mic wiring - that is where I started. ? Uniden BC-645 is a Cobra compatible electret 4 pin mic wiring 1-GND, 2-MIC, 3-PTT, 4-RX - I have 1, 2 and 3 wired correctly, I believe, per my enclosure instructions.?? Sadly - no 3.5mm plug at hand at the moment - but I will wire up the mic and PTT button that came with the kit and test. Curious if anyone has experience with this mic. Dean KK4DAS |
Re: Calibration success
#ubitx
#calibration
¿ªÔÆÌåÓýSorry. ?Think there is voltage only when the ppt is keyed for the uBitx?Dan On Aug 11, 2019, at 5:55 PM, Dean Souleles <dsouleles@...> wrote:
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Re: Calibration success
#ubitx
#calibration
¿ªÔÆÌåÓýWire the mike that came with the rig and use the plug to the phono mike input. ?Haven¡¯t looked at the audio diagrams recently but think the dc voltage should show up on the mike line when it is keyed by the ppt. ?Not sure about your wiring instructions that came with the chassis box. ? You should be able to measure a dc voltage on the mike line. ?? Also get on the internet and look up the connect wiring for your specific Mike. ? Dan W3BU? On Aug 11, 2019, at 5:55 PM, Dean Souleles <dsouleles@...> wrote:
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Re: Calibration success
#ubitx
#calibration
Step by step....
I have +5 volts on 4 pin connector pin 3 when the radio has power - it measures +5 against either Pin 1 or Pin 2 or the case. Again - from the Uniden/Cobra wiring that I have found on the net it should be? 1. Gnd 2. Mic 3. PTT Is there supposed to be voltage on the PTT line or am I possibly cross wired? (as an aside - I really dislike mic wiring!) And there was no 3.5mm pig-tail or connector in my kit - I presume I need a stereo plug - I can harvest an old PC speaker wire. ?? Just need to get that wiring right! Dean KK4DAS Dean? KK4DAS |