modifying microwave modules 70cm - ch36 converters

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g8xzd
Posts: 5
Joined: Wed Aug 01, 2012 5:06 pm

modifying microwave modules 70cm - ch36 converters

Post by g8xzd » Tue Oct 30, 2012 11:20 pm

Hi I have read the old microwave modules 70cm-ch36 converters can be modded to work with satellite receivers
ie the output is circa 970MHz instead of TV ch36. Has anyone tried this and had any success?
There was also a Fortop version of the same converter - from memory it had its output on Ch40 - both very similar though.
I have seen others using the directtv module but ordering via eBay is too much of a hassle.

Many thanks. Ian.

M0DTS
Posts: 656
Joined: Sun Feb 24, 2008 9:03 pm

Re: modifying microwave modules 70cm - ch36 converters

Post by M0DTS » Thu Nov 01, 2012 11:02 am

Hi Ian, yes i did this some time back but never really used it after Finding the directv converters..

See attached image for my crude solution:
Oscillator is 125MHz TTL module on 5th Harmonic with output filter tuned at 625MHz, this replaces the original oscillator circuit.
Te two tuned lines are around 1/3 of original length and tuned up for 1062MHz.

Not sure of the conversion gain now as i have never tried it in anger!

Rob
M0DTS
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g8xzd
Posts: 5
Joined: Wed Aug 01, 2012 5:06 pm

Re: modifying microwave modules 70cm - ch36 converters

Post by g8xzd » Thu Nov 01, 2012 5:47 pm

Many thanks Rob I'll give that a go. Cheers. Ian.
M0DTS wrote:Hi Ian, yes i did this some time back but never really used it after Finding the directv converters..

See attached image for my crude solution:
Oscillator is 125MHz TTL module on 5th Harmonic with output filter tuned at 625MHz, this replaces the original oscillator circuit.
Te two tuned lines are around 1/3 of original length and tuned up for 1062MHz.

Not sure of the conversion gain now as i have never tried it in anger!

Rob
M0DTS

G8KFW

Re: modifying microwave modules 70cm - ch36 converters

Post by G8KFW » Thu Nov 15, 2012 9:19 pm

Hi All
re FORTOP ATV converter the model number is TVC 435/40
I/P Freq 425-445 O/P Freq channel 38 – 40 Gain 25 db

I do have the cct diagram , parts list and a Blank PCB to make copies from. So if a number of you want to build them
and someone wants to Take the Project on please contact me
Paul Bicknell radio@bicknells.f2s.com mobile 07719 208048 :mrgreen:

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keng8vdp
Posts: 143
Joined: Tue Mar 15, 2016 8:51 am

Re: modifying microwave modules 70cm - ch36 converters

Post by keng8vdp » Mon Dec 23, 2019 10:29 pm

Well, I know this is an old topic, however, does anyone have an easy way of producing 1v p2p out of said converters as this might be a more useful method. Yes, there are some conscientious ATV operators round here who would be interested "cough" just for technical reasons.

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