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Re: uBitx diagnostic document from Facebook group
#ubitx
I agree, John. I just found this. I think it ought to be on the website, readily available to all. I wish I had had it weeks ago..
-- 72 and God bless KD4EPG |
Re: Nextion 3.2 for CEC 1.097
#ubitx
I have modified the CEC Nextion screen for my 3.2"
3.2 Enhanced HMI 3.2 Basic HMI 3.2 Enhanced TFT 3.2 Basic TFT |
Re: uBitx low audio all of a sudden
UPDATE
I found the low receive was due to a bad NANO. I have a spare Raduino board and put it in and it worked, replaced the NANO on the other Raduino and it worked. Problem now is? I have no XMIT power on CW or SSB. Any suggestions where to start looking? This radio was working fabulous yesterday. I really don't understand. It is like gremlins got in it last night.. lol -- 72 and God bless KD4EPG |
Re: 80 meter bandpass filter
jim
On Monday, August 20, 2018, 3:11:36 PM PDT, jim via Groups.Io <ab7vf@...> wrote:
On Monday, August 20, 2018, 3:03:15 PM PDT, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
On Mon, Aug 20, 2018 at 02:45 PM, Jim Tibbits wrote: Output on dummy load after filter mod?? ... almost makes it Jim |
NEW DISCUSSION GROUP SPECIFICALLY FOR HOMEBREW TEST EQUIPMENT
The new discussion group has been formed.? ? Three persons have volunteered to be moderators (Gilles, Dennis, and Jim).? I will make them moderators just as soon as they have subscribed to the new group.? Concept for this group is that it will focus on Amateur Radio Test Equipment that you have designed and built. Operation and testing with homebrew test equipment is also a suitable topic.? The intent is to stimulate design and construction of near-lab-grade but inexpensive test equipment for use by radio amateurs.? I am guessing that a lot of this will involve micro-controllers, but we shall see where the discussions take us.? Arv? K7HKL _._ |
Re: 80 meter bandpass filter
jim
On Monday, August 20, 2018, 3:24:33 PM PDT, Bill Cromwell <wrcromwell@...> wrote:
Hi, If I recall correctly the forty meter filter also passes 30 meters, and the 20 meter filter includes 17 meters. The materials are starting to arrive for my external filters and I intend to build one for each band and not include two bands per filter. 73, Bill? KU8H Just moved it down a bit ... Jim |
Re: Intermodulation Performance
Your results are disappointing as I'd suspected they would be.
The amplifier chain seems ot struggle to make power and the quality of the power is poor. What also is suspect is the two IF stage 12 and 45Mhz have excess gain and the mixers are likely getting over driven.? How much excess depending on how you count it overall at least 16db.? I don't believe that helps except to make up for low gain in the transmit chain. Allison |
uBitx low audio all of a sudden
I have a v3 uBitx that has had some issues in the past but these were all worked out, to include changing out the TDA2822 to another version of that chip. I have been working with this radio for several weeks now and it has been working fine.
Today when I went to use it, the receive audio is extremely low. I can hear it in an earbud if I turn it all the way up, but the side tone is so loud then that you can't stand it. I havent made the side tone volume fix yet. The output is at rated output on CW but I have zero output on SSB. The rig was off all day and when I turned it on, this is what I found. Then antenna is good, everything seems to check out fine except the radio. Can someone point me in the right direction? Thanks 72 -- 72 and God bless KD4EPG |
Re: Bitx40 Specifications?
Gordon Gibby
¿ªÔÆÌåÓýI quickly took information from others and created my own little sketch that allows me to do 80 m as well, made a few hardware changes for that and bought an output low pass filter. ? Turn it on¡ª-learning starts!
Gordon
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Bitx40 Specifications?
?I built my Bit40,? but was looking to find some specifications.? Is there a good list of specifications???? The HF Sigs site has some for the uBitx but missing on the Bitx40.?? For instance what should be the frequency range, bottom to top end???? I wanted to know if it goes to the right limits on both end.? Just some verification before I do any mods.
Thanks 73, KM4OLT Michael |
Re: 80 meter bandpass filter
Hi,
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Show quoted text
If I recall correctly the forty meter filter also passes 30 meters, and the 20 meter filter includes 17 meters. The materials are starting to arrive for my external filters and I intend to build one for each band and not include two bands per filter. 73, Bill KU8H On 08/20/2018 06:11 PM, jim via Groups.Io wrote:
--
bark less - wag more |
Re: 80 meter bandpass filter
jim
On Monday, August 20, 2018, 3:03:15 PM PDT, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
Yes, corner is set a high so it can be used on 60m too. On Mon, Aug 20, 2018 at 02:45 PM, Jim Tibbits wrote:
Aha!!!! photo of "80 meter" bandpass filter on my ubitx ...L20, L21, L22 as swept? ..corner frequency is closer to 6 mhz than 4 _._,_._,_
Meh on 60?? ..I'm moving it
JIm |
Re: 80 meter bandpass filter
Yes, corner is set a high so it can be used on 60m too.
toggle quoted message
Show quoted text
On Mon, Aug 20, 2018 at 02:45 PM, Jim Tibbits wrote:
Aha!!!! photo of "80 meter" bandpass filter on my ubitx ...L20, L21, L22 as swept? ..corner frequency is closer to 6 mhz than 4 |
Ubitx los noise
#ubitx-help
Miguel Villamor
Hi, I try to explain that happend to my uBitx, in 40 m dont have trouble , the signal its strong, but when advance in superior bands 20, 15, 10, the noise its very low, I supose was the antenna, but prove with ft-817 and have a strong signal in this bands, I try the BFO settings, gain some signal streng in 20 m no more, any ideas??, Sorry for my English, 73 from Chile.
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Re: BITX QSO Afternoon/Evening, Sunday, August 19, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
Punctuation, lad! For lack of a comma, it reads as JW4JM. Still, a neat call. My previous, a selection from those available, was ZL3LH (different region, and vanity calls not implemented in regulations), 'Left Hand' to balance me (dexter being Latin for the right side/hand/arm: skill and sword-arm strength). Present call is a 'vanity', and quite pleasantly fluid to the 'fist'...
73 de ZL2DEX |
Re: Intermodulation Performance
Warren Allgyer
Allison Maybe another way of looking at it: Testing on 80 meters, through a very sharp bandpass filter that limits harmonics and spurs to -60 dBc or better, I set the Drive level to produce +37 dBm on CW. I then put a single tone at -43 dBV into the audio input to get +30 dBm output on SSB. I then increased the tone input in 1 dB increments until I achieved 1 dB of compression. That happened at an audio level of -34 dBV, 9 dB higher than the level to make one watt, and the RF output with that input was +38 dBm. An increase of 9 dB of audio produced an increase of 8 dB in RF output; 1 dB of compression. I then added a second tone at the same level and measured the difference between one of the tones and the first adjacent product: -15 dB. Opposite sideband products were less than 30 dB down from the primary tone level. Operation of my radio at the 1 dB compression point results in unacceptable (to me) IMD as well as unacceptable (to everyone) splatter in the opposite sideband and outside the filter sideband on the desired sideband. I could not achieve my desire for -24 dB for the first IMD product with any more than -41 dBV of audio drive which produced an RF output of 1.6 watts. |