Advice on QO-100 TX using Portsdown 4

[M0MBO]

Hi,

I currently have a NB QO-100 station operational and now plan to add DATV WB capabilities.

I have Portsdown 4 (sw v. 202311130) and Minitioune v2.

Looking for advice on two TX related items please, in order to take the right path forward:

1. Pluto or Lime?
2. Recommended PA?

Many thanks,
Malcolm
M0MBO

[Basil]

Much or most of the current firmware and software development seems Pluto specific, so I would choose a Pluto for that reason.

PA wise much will depend on the size and efficiency of your dish as that will govern how much power you need to generate a decent signal, especially in some of the modes that need some extra push.

The choice of PA will also depend on whether you want turn key ready, designed for the frequency devices like those from PE0RKI, or a modest power similar device from SG Labs, or if you have the ability to modify a commercial amplifier to suit a frequency it's not designed for yourself and test it.

Ready modded and tested commercial amps often of Polish origin can sometimes be had from the ever helpful James (Jim) Smith G7NTG.

Ready built small USB / 5 volt powered pre amps are available from Analog Devices, the makers of the Pluto.

Happy Christmas and a healthy and prosperous New Year to all.

Chris 2E0ILY

[M0MBO]

Thanks Chris for helping me with this - the info is exactly what I needed.

73 - Malcolm - M0MBO

[Basil]

You're most welcome. One thing I would add is don't skimp on the PA power suppy! I bought a cheap Chinese switch mode supply for my PA (SG Labs 20 Watt jobbie) and it blew up after a few months, with uncontrolled output voltage. It in turn blew the input power supply electrolytic in the PA, luckily it was a fairly straightforward if fiddly fix, and no other damage was done.

I now only buy branded switch mode supplies from reputable sources.... Have fun.