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Re: uBITX - Limiting power output
¿ªÔÆÌåÓýDon't know for sure. ?Christmas party this afternoon so be tomorrow before much else gets done. On Dec 2, 2018, at 12:12 PM, AndyH <ahecker@...> wrote:
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Re: uBITX - Limiting power output
¿ªÔÆÌåÓýDon't know for sure. ?Christmas party this afternoon so be tomorrow before much else gets done. On Dec 2, 2018, at 12:12 PM, AndyH <ahecker@...> wrote:
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Re: Missing link bitx40 circuit diagram
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On Sun, Dec 2, 2018 at 09:26 AM, Simon wrote: Would hfsignals please restore the missing link in? |
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Re: uBITX - Limiting power output
Two watts will deliver 5-7 watts. The 2 meter transverter by TenTec I think has a bandpass filter at the input which might filter out the spurs on SSB (CW should be fine in any case). Il 02/dic/2018 18:47, "Curt via Groups.Io" <wb8yyy=[email protected]> ha scritto: Yes I know the 1208 as it was hard to adjust my then hf rig to not overdrive the transverter on ssb, when it could be fine on cw. My 1208 did best with only 2 watts drive on ssb. The stock ubitx has no transmit drive adjustment. I would add a transmit drive pot before the PA. You may need someone to listen to your signal to get the level correct, unless you have a peak power meter. |
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UbitX audio hiss but no rx
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Hiya, |
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Re: RF power chain mods and improvements..
Joe Puma
¿ªÔÆÌåÓýI only had a flat tip for my weller iron. I got a pointy tip recently and found that the tip didn¡¯t stay tinned for very long and it didn¡¯t heat the solder as quick as my flat tip. I¡¯ve soldered some small components with success with the flat tip, even as large as it was. A good magnifying glass and a steady hand helps.?Joe On Nov 25, 2018, at 3:54 PM, ajparent1/KB1GMX <kb1gmx@...> wrote:
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Re: uBITX - Limiting power output
Yes I know the 1208 as it was hard to adjust my then hf rig to not overdrive the transverter on ssb, when it could be fine on cw. My 1208 did best with only 2 watts drive on ssb. The stock ubitx has no transmit drive adjustment. I would add a transmit drive pot before the PA. You may need someone to listen to your signal to get the level correct, unless you have a peak power meter.
The 2m transverter from tentec has a leveling loop, it is much better at managing drive level. But sure having a qrp rig with a known 20m output level is useful here. For now, assemble your ubitx and enjoy it. I suggest avoiding bands above 20m until you have added mods to improve spurious. Curt |
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Re: uBITX - Limiting power output
Depends on how much power you have on 14Mhz, a 10w non inductive fixed attenuator is best, to be on the safe side - 3db. Il 02/dic/2018 17:39, "Charles French" <crayp0st@...> ha scritto: I want to use my v4 uBITX (under construction), with a Ten-Tec 1208 6m Transverter (SSB) that requires input of MAX 5W. What¡¯s the best way to limit the uBITX output power? Ideas appreciated, Thanks. |
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Re: I cant seem to find
Have you looked at the Hamskey.com (Ian Lee KD8CEC) web site?? The files for his firmware versions include options for bath parallel and serial LCD interface.? I also believe that there was a modification that could be made to the source to change the Si5351 to the I2C link, and change the address for the Si5351 chip.
The files are on Git Hub: Sorry, but I do not remember where on Ian's site that I read about the source modification.? There may be comments in the source files from Github. Hope this helps Evan AC9TU |
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Signal level at TP1 for current batch of ubitx and also bitx40
We want to buy either a uBitx, multiple band or bitx40, single band, for "experimental use", apart from normal use.?
We have a Arduino DDS AD9850 board programmed to generate psk31 RF at hf freq. It transmits about 1 mili watt, 0 dBm, to a dummy load ok. We plan to cut pin 1 of T2, top left corner of circuit diagram of ubitx, at below link, to isolate the rest of the circuit. The dds signal will go into TP1. Appropiate relay will be energized. Singal from dds has been cheched and was clean enough, as it has its own filter also added, the ubitx has filter L1 to L4.? Before we buy it, would appreciate advises from the forum.? Will the same mod work on the single band bitx40? I was told the diode mixer "generally" work at -16dBm. Will that be the case for these 2 radios?? It will be simple to use resistor attenuator, if dds output is too strong. If it is too weak, we are not too confident to add an amplifier ourself. Any advises on this will be appreciated Singal into the 2 stages PA will be clean enough. Likely cleaner than the ubix as the diode mixer generate some unwanted signal. Any idea on the output spectrum purity (pa and post pa lpf) 73 Simon |
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Re: Spectrum purity of uBITX and BIT40
Hard to tell, for what I know, there have been different production batches, each board was checked but may slightly behave differently from others. Current production should have solved relays issues that were mainly responsible for insufficient odd harmonics suppression. For older versions like mine, ver 3 a simple change with better relays (Axicom) resulted in a better harmonics suppression. As for TX purity it is not an IC7300. Speaking loud and very close to the mike results in splatters, TX imd was found being not too good. There is no ALC. My impression is that modulation is effective (the filter is narrow and if BFO is set far enough it sounds pretty dx) and I had received good modulation reports. In a nutshell if one can only listen to classical music will probably dislike it, and this is why I love it! Il 02/dic/2018 09:03, "Simon" <simonhk7@...> ha scritto: May i ask what is the output spectrum purity, supression of harmonics etc., for ubitx multiband and the single 40m band bit40 |
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Re: Nextion Display: Source ???
All the best Balan. ?I had one such with TJC 3.5 display and Aliexpress supported my cause and of course I sought partial refund, as mian display still works and only the touch glass broken. On Sun, Dec 2, 2018 at 12:46 PM Dileep Balan <dileepbalan@...> wrote: Thanks VU2POP, Snowist and DV3RWR for your comments. |
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Re: The Exseed sat update
Thanks RAJ, ?It relieves us from the frustration regarding the? issues under concern. wish all success, post launch and? let the sat serve the ham community at large. regards sarma ?vu3zmv On Sun, Dec 2, 2018 at 12:39 PM Raj vu2zap <rajendrakumargg@...> wrote:
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_Dave_ AD0B
Jim Sheldon
TA2WK