Other SOTA sites: SOTAwatch | SOTA Home | Database | Video | Photos | Shop | Mapping | FAQs | Facebook | Contact SOTA

GM/SS-191 Cairnharrow and VHF preamplifiers


#1

Back up to my summer “local” hill for the first summer activation. I was surprised by how dry the hill was - a real difference from last year when everything was very soggy at this time of year.

Many thanks to all chasers and to Don G0RQL and Roger G4OWG for the (simultaneous) spots.

It was particularly good to start with an S2S with Tony G7OEM/P on Rombalds Moor G/NP-028; I could hear him working several people so was glad to be able to get in there. Don then directed me to a clear spot up the band for which many thanks.

I was glad to be able to provide some GM on 2m to those rather further south! - I’m hoping for more VHF and up this year, especially once I have the 23cm transverter working. I really ought to get a little 70cm linear organised as well. Those hills in south west Scotland have a great take off for much of England.

Contacts were made using the homebrew linear on the FT-817 giving 25W or so to a 5-ele homebrew Yagi (DK7ZB design). This year I have a little preamp inside the linear box as well, and suspect that some of yesterday’s contacts would not have been on without it - it gives one or two S points of extra signal. However, I’d be interested to hear what other FT-817 VHF SSB-ers have to say about preamps on the FT-817. I think I really need to make mine switchable so I can easily hear the difference, and cut it in only when absolutely necessary. Any thoughts folks?

The log will go up once the database is back.

73
John GM8OTI


#2

In reply to GM8OTI:
Hi John
It makes QSO’s even more satisfying using your home built gear I am sure, aerials are really as far as I have gone.

From my experience with the 817 it may well be useful to switch the preamp eventually, Ive had a few question marks over the 817 and its strong signal handling on 2m, 70cm. I thought it was just my 817 but when I borrowed one I got the same sprogs from very strong stations when on top of the hills, nothing on my 706. You may want to let me know if you have ever noticed the same thing? 817 is superb for the money, no complaints.
A “good” preamp makes a difference to the RX some none at all, you will know that a slight increase in noise when you switch it in is what we are after, ive found that the old commercial amps with a BF981 sometimes seem to be better than the newer GAAS fet supposedly low noise ones, they generate alot of noise and sometimes swamp the front end.
73, hear you during the coming weeks.
Robert
GM4GUF