Re: ubitx spurs? Added LPF
This is a V3 that has new relays and
the L5/L7 fix and working on the LPF
that I believe is before the mixer, but I'm not sure.
I've been taking measurements at each step.
By
John Sutter
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#67789
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Re: ubitx spurs? Added LPF
John
very good - I am interested in your results on this, and which ubitx version you have.?
on 12m you might notice 2 spurs on either side of the carrier about 5 MHz apart,? the v5 comes with a
By
Curt
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#67788
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Re: ubitx spurs? Added LPF
Good point. Earlier in this thread it
was recommended that I add
a LPF to get rid of the spurs on 15, 12, and 10m.
It was my understanding that the following (from Ashar I
By
John Sutter
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#67787
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Re: ubitx spurs? Added LPF
John
You aren't clear in this message which spurs you are trying to solve, nor where you are putting this new filter?
If this is an added 45 MHz filter, adjacent to the mix to and from RF, then its
By
Curt
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#67786
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Re: ubitx spurs? Added LPF
I was about to dig into my parts bin searching for toroids and
I remembered I had those left over.
I'll probably have to order some 30 uH parts.? 27 and 33 are easy to get locally, 30 maybe
By
John Sutter
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#67785
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Re: ubitx spurs? Added LPF
John,
Very neat job on L5 and L7.
Make the 45MHz IF new filter with SMD parts. What seems to be the culprit is any vertical wire leads in that area
causes trouble. Solder the SMDs directly on the
By
Raj vu2zap
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#67784
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Re: ubitx spurs? Added LPF
Ok, I have mounted the LPF filter in a Manhattan style without any glue so
I had more flexibility in positioning the toroids, which are very light. I
am not sure I understood your spreadsheet. The
By
iz oos
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#67783
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Re: ubitx spurs? Added LPF
Well, that didn't go well.
Looking at it, the two toroids on the left are a little close.
I have a layer of grounded copper foil between
the PCB and the filter (insulated of
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John Sutter
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#67782
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Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio
#ubitx-help
#ubitx
By
Don Stewart
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#67781
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Re: Microphone choices
I use this ,from qrpkits.com{Pacific Electret Microphone kit.Works great
[image: image.png]
Dale/ka5who
By
ka5who@...
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#67780
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Re: Standalone signal analyzer
Update: success with the signal analyzer install! I have moved into my new shack, but no antenna feed through? yet. So will test tomorrow. A lot accomplished today! Waiting on the new bc645
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Kelly Mabry <kmabry2007@...>
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#67779
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Re: Standalone signal analyzer
I thought about that but I wanted to reduce the stress off that 7805 on the raduino, so I added the buck converter to run the display and the extra nano. I have loaded the signal analyzer software on
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Kelly Mabry <kmabry2007@...>
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#67778
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Re: Standalone signal analyzer
Total current would not be even 1 amp, more like 100 ma.? Should not be a problem.? I do know that Dr Lee ran all of the devices off of the same Raduino supply, just added a heat
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Evan Hand
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#67777
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Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio
#ubitx-help
#ubitx
I just thought of another possible problem, Q74 might be shorted.? This would follow the symptom of the injected audio at the volume control not getting to the earphones.
I had feedback is and
By
Evan Hand
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#67776
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Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio
#ubitx-help
#ubitx
If you have access to a frequency counter or an oscilloscope I would next check the 3 clock signals coming from the Raduino to the uBitx board.?
If you measure approximately 45 MHz- dial setting in
By
Evan Hand
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#67775
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Re: New siglent on the way
Thank you guys, but I already had a series of adapters, series of of BNC attenuators, a 6 dB N rated at 2 watts and heathkit Cantenna with a homemade attenuator and now a commercial 50 W dummy load
By
Gordon Gibby <ggibby@...>
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#67774
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HERE IS A cap (CHEAP AS POSSIBLE) WAY TO CONNECT UbITX OUTPUT TO A SCOPE, METER, FREQUENCY COUNTER OR SPECTRUM ANALYZER
This utube sight has several videos on DIY test gear and dozens on radio repair.
https://www.youtube.com/watch?v=RLwZFlP9wr8
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Michael Mitchell <mitchellmichaelh@...>
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#67773
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Some are looking for dummy ;load for uBitx here is watts up
W8TEE designed this dummy load and published it on a webpage (which now seems inactive.) and QST magazine
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Michael Mitchell <mitchellmichaelh@...>
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#67772
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Re: Raduino with a different SDR?
I use gqrx on my Ubuntu laptop. I've written several Perl and wxPerl
applications that use the UDP interface to implement various scanner
functions. The UDP interface implements a subset of the rigctl
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James Lynes <jmlynesjr@...>
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#67771
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Standalone signal analyzer
Hi guys it's Kelly I'm thinking of trying to add to Standalone signal analyzer to my ubitx. I have added a buck converter from 12 volts down to 5.1 volts at 3A. I currently have it successfully
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Kelly Mabry <kmabry2007@...>
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#67770
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