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Re: New 10 GHz LNB

Posted: Fri Nov 23, 2018 7:37 am
by dh2va
Excellent work!

Re: New 10 GHz LNB

Posted: Mon Nov 26, 2018 4:09 pm
by G4EWJ
Dave, I forgot to ask which supplier your 1609 code LNBs came from.

Brian

Re: New 10 GHz LNB

Posted: Fri Nov 30, 2018 5:38 pm
by g0mjw
I just received 3 more 1609 single OSLO LNBs from Amazon, sold by HM-Sat-Shop for £8 each. They have a single 25MHz crystal, just like the last one I bought.

Mike

Re: New 10 GHz LNB

Posted: Fri Nov 30, 2018 11:59 pm
by G4EWJ
They don't appear to have the OTLSO unfortunately.

Brian

Re: New 10 GHz LNB

Posted: Sat Dec 01, 2018 6:37 am
by G8DKC
Found this twin on Ebay 192108842161

I did the 26mhz and 27.5 mods on one a while back giving me aprox 980mhz and 438mhz for 10.4ghz.

Can't find your Cat talk Brian on the original mods.

I take it the Octagon OTLSO PLL Optima is ok for locking mods.

Peter

P.S Have gone back to other posts, possible boards for Ref input, mods etc.

Re: New 10 GHz LNB

Posted: Sat Dec 01, 2018 12:04 pm
by g0mjw
My boards turned up from PCB Way much quicker than I expected.
PCB_Bias.jpg
PCB_Bias.jpg (361.94 KiB) Viewed 6524 times
I have built one up, I haven't got all the right parts so a little bodging was needed, especially around the BNC/F connector, but it seems to be working. Needs cleaning up a bit. I will design an update based on what I have learned building the prototype. What to do next, not sure.


Mike

Re: New 10 GHz LNB

Posted: Sat Dec 01, 2018 7:12 pm
by G4EWJ
I would be interested in a couple of the next version Mike.

Brian

Re: New 10 GHz LNB

Posted: Sat Dec 01, 2018 7:35 pm
by G4EWJ
Peter, I think this was the presentation. https://www.youtube.com/watch?v=gC9IqqEEhwY

I should think that locking would be fine on the OTLSO.

I've been looking around for crystals to bring the NB section into 432MHz, to use an FT817. For the 27MHz version, the best I've found is 27.85MHz, which brings the NB section to 432.605MHz. I don't know if the 27MHz version is stable with that high a crystal.

For the 25MHz version, the best I've found is 25.78125MHz, which brings the NB section to 434.862. Again, I don't know if it would work. It would also bring the WB section down that low.

You'd probably have to use reverse DDS to externally lock those frequencies.

Unfortunately both crystals are from Mouser, so I'll have to wait until I need enough stuff to get the free postage.

Brian

Re: New 10 GHz LNB

Posted: Sat Dec 01, 2018 9:37 pm
by G8DKC
Thank you Mike for view of your circuit and new board, intrested in a couple of boards if they come available.

Also Brian for link, that's the one :-) and your information on modifications and limits.

Have done some catch up today on Batc and other forums.

Peter

Re: New 10 GHz LNB

Posted: Sun Dec 02, 2018 8:06 am
by G8DKC
Off the wall LNB lock with the Si5351A Synthesizer

I gather that the Si5351A kit supplied by QRP Labs can be locked to 10Mhz.

Link to that post

https://groups.io/g/QRPLabs/topic/is_th ... 0,26746229

http://qrp-labs.com/synth

https://qrp-labs.com/vfo.html

Square wave output will cover 25 - 27mhz etc.

I have no experience with the Si chips, would this be too noisy?

That is if the concept worked :-)

Peter