Has anyone tried to modify the BITX40 to work on 630 M?? It looks like if one changed the bandpass and low pass filters, and changed the VFO to 11.5 MHz it should work.? For USB you'd use the sum from the BFO mixer and the difference from the VFO mixer.? If this works, it would make a nice transceiver for 630 M digital modes.

Fred WA0GMH

开云体育

?I don't think anyone has tried it but it should work reasonably well.....tuning an ANTENNA for that band is probably the bigger issue.....

Cheers!!

gordon

Hi Gordon,

Yes, the antenna will take some work.? I plan to start small (inefficient) and work my way up.? I have an Ultimate 3S that works well on 630 M with WSPR, but I'd like to try some JT-9 on 630 M.? I've ordered the QRP Labs VFO kit that uses the SI5351.? I plan to stabilize (discipline) the VFO with a GPS, like with the Ultimate 3S, so it should be very stable.? The VFO can then be used to provide the two frequencies for the converted BITX40.

Fred

Should work, Fred. See what I did with QRP Labs filters in the Multi-Band BITX40 link in my signature below. It works very well down to 80m and I'd love to see what you do for 630m. I'd like to try 630m and 2200m as well but alas I have no room for such an antenna!?

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Ryan Flowers - W7RLF

Hi Ryan,
I'm anxious for my BITX40 from HFSignals and VFO from QRP Labs to arrive.? I've been calculating what I need for the band pass and low pass filters and think I have the toroids and caps in stock.? I plan to try using a 160 M inverted L to start.? It won't be very efficient, but I can copy quite a few WSPR signals on 630 M using it.? I still have to build a matching network so it's resonant around 475 KHz.? It's been below zero much of the time, so I won't be working on the antenna anytime soon.