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Re: BITX VXOs


Ron Brink
 

Ola Miguel,
I like to see some picts of your super VXO's Miguel. Great coverage with only 3 xtals. Is the output stable over the whole range? Do you use one or more (switchable) coils in series with the xtals to cover the range?
?
I have shielded my BIT17 VFO (soldered some unetched PCB's around it) and now the VFO with Huff&Puff is also stable when I force it out-of-tune e.g. by placing the desk-lamp just above the vfo. Added one picture in the photobox.
?
73
Ron
PA2RF

Miguel Angelo Bartie wrote:

Hello

I build 3 VXOs called "hipervxos" for 40m, 20, and 10m to use with BITX,
They use a classic Colpits oscilattor with 3 parallel xtals and a
series? inductor (special) and a series variable capacitor
For 40m I use 3 x 3020 kHz xtals and the actual range is 2068 to 3010kHz
For 20m I use a commercial 3 x 4194 kHz xtals covering 4190 to 3990 kHz
For 10m I use a commercial 3 x 18432 kHz xtals covering 18400 to
18000kHz.
The BITX 40m is running good, the 20m still in test (but is ok too),
and the 10m version I built only the VXO.
The exciter and the PA are the same I change the vfo, the band pass
filter and the low pass filter.
I will make some pictures and I will post here.

73 from PY2OHH Miguel







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