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23cm PA

Posted: Tue Mar 14, 2023 10:36 pm
by M0PAI
Looking for a 23 cm PA to use with Pluto Langstone and Portsdown ATV.

Have a broadband usb c 1w (500 mw) amp on way but want a little more power.

Re: 23cm PA

Posted: Wed Mar 15, 2023 7:59 am
by radiogareth
One of the Mitsubishi brick PAs would be an easy solution with that much drive available. Enigma Components sell the control board and brick.
https://www.enigma-shop.com/component/h ... es-modules

Gareth

Re: 23cm PA

Posted: Wed Mar 15, 2023 6:39 pm
by M0PAI
Thanks Gareth,

Is there anywhere that has a list of what's actually needed and how it goes together?

The PCB in the link is out of stock.

Cheers

Re: 23cm PA

Posted: Wed Mar 15, 2023 7:13 pm
by radiogareth
Thats a shame, there are others on eBay from Europe I think, maybe Aliexpress too. TBH the boards are pretty much plug and play usually with 12VDC and a pin to ground to enable the bias. Have a look at this article which may help, or not....P38 CQTV issue 272

Gareth

Re: 23cm PA

Posted: Thu Mar 16, 2023 4:45 pm
by g4kzy
Enigma's web site says they have 50 boards in stock today.

Or order both the module and PCB from Engigma's ebay store:

https://www.ebay.co.uk/itm/Genuine-Mits ... 3816893697

I bought a similar one from SAM G4DDK once - which I used for a 2m amplifier but I don't expect he has any these days.

73,

Paul G4KZY

Re: 23cm PA

Posted: Fri Mar 17, 2023 9:10 pm
by M0PAI
Thanks Paul,

Appreciate the help, looks like a simple option to get started 👍

Thanks
Adrian

Re: 23cm PA

Posted: Mon Mar 20, 2023 9:10 pm
by M0PAI
If the Mitsubishi amp is used, do you take a PTT line from the Pi pin 40 or from another pin?

Re: 23cm PA

Posted: Mon Mar 20, 2023 10:45 pm
by G3GJA
Adrian

Pin 40 on the PD4 goes to +3.3v on transmit ready. Use that via 4k7 to the base of an NPN transistor with grounded emitter. In the collector you can put a low current 12v relay (with diode across the coil) and use the common and N.O. contacts to turn on 12v to the bias/power control pin on the Mitsubishi amp.

Alternatively. use a PNP transistor with emitter to +12v and collector to the bias/power pin on the amp and connect the base via a10k to the collector of the NPN if like me you don't like relays.

If you have some form of PTT switching on the PCB, such as the Enigma one, try connecting the collector of the NPN to the PTT input or use the relay and then use the contacts to do the switching.

Clive

Re: 23cm PA

Posted: Tue Mar 21, 2023 8:19 pm
by M0PAI
Thanks Clive,

Was hoping it was a simple connection from the Pi to Mitsubishi PCB board.

I'm not the most technically minded :lol:

Re: 23cm PA

Posted: Sun Apr 02, 2023 6:16 pm
by M0PAI
Now sorted, amp purchased
Thanks all for the help