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Re: Equipment for new 4m band

Posted: Sat Jul 28, 2018 6:12 pm
by G8PEF
Noel - I'd be up for buying the mixer and PGA103 if you were stocking them.

John
PS - I've sent you a PM this evening, Noel

Re: Equipment for new 4m band

Posted: Sat Jul 28, 2018 6:33 pm
by g8vpg
Yes, please do stock them (and perhaps two PGA103's for every mixer because they are not the most reliable device in my experience!).
Shaun.

Re: Equipment for new 4m band

Posted: Sat Jul 28, 2018 7:21 pm
by g0mjw
g8vpg wrote:
Sat Jul 28, 2018 6:33 pm
Yes, please do stock them (and perhaps two PGA103's for every mixer because they are not the most reliable device in my experience!).
Shaun.
Perhaps if the PGA103 isn't reliable try something better? I don't really know what devices might suit, spf5189z perhaps? The GALI 59+ used to be one of my favourites but it would need the choke replacing with a 127 ohm resistor and the regulator bypassing.

Re: Equipment for new 4m band

Posted: Sat Jul 28, 2018 9:49 pm
by g8vpg
I've had a number of PGA103's fail on boards provided by G4DDK, but he tends to run them at 5V. Perhaps running them at 3.3V will make a difference? When they work, they are good though.
Shaun.

Re: Equipment for new 4m band

Posted: Sat Jan 12, 2019 1:08 pm
by radiogareth
Just wondering if anyone has a BOM for Farnell or digikey that fills the 71 MHz rx upconverter from CQ260. Farnell or digikey don't seem to list either U1 or U2, unless I'm typing something in wrong.
Looking for an alternative I have a Spectrum Comms Receive Converter RC4-2 and recall reading that the LO isn't 'ideal' being at 75MHz. Whilst no RF engineer I can't see any issue with hiking the LO somewhere more suitable (100MHz 50ppm crystal oscs on eBay for under £5) and changing the output filter to something a bit tighter on the new frequency. The circuit diagram shows the mixer as made of BAT42 diodes and a BF964 in between a pair of tuned circuits makes the input.
LO available from the AD synth in my Portsdown.
Or am I missing something????
TIA
Gareth

Re: Equipment for new 4m band

Posted: Sat Jan 12, 2019 1:30 pm
by M0SKM
Hi Gareth,

I built two of Mike's converters and both items you're looking for came from Minikits in Aus. Can't help with the oscillator as both mine have ADF4350 boards built in.

Steve

Re: Equipment for new 4m band

Posted: Sat Jan 12, 2019 3:46 pm
by radiogareth
Thanks Steve. Think I need to look up an easy way of setting up the ADF4350 to a specific freq to make it stand alone, although TBH a 100MHz xtal will be a simpler solution.
Gareth