RTTYing in A71 Land

Well,

Its been snowing hard in the UK (so I understand), but I'm stuck in A71 land this weekend....

The Qatar Amateur Radio Society were doing a stall at an exhibition recently, I called by to see them, here's the set up:

I've actually spent some time at the QARS main site today, you may remember I visited them a while ago:

http://g0mgx.blogspot.co.uk/2013/02/a7-land-a71a-ah-qatar.html

I've been running RTTY using one of their FT-2000s. You may recall I made an interface for my FT-450 a while back:

http://g0mgx.blogspot.co.uk/2013/01/hows-interfacing.html

Well, here it is on top of the FT-2000 - plus an adapter for the rig end of the cables:

So been running on 20M RTTY today with the callsign A71A. Been quite hard work as at times there were many stations calling, but no single signal decoding, I guess I perhaps need to consider working split next time.

Fun though, egh?

Where do the knots come from?

Well,

I've been checking some wiring today; there's a great deal of it in my shack and it's always in a spectacular knot!

I saw some SWR movement during the XE contest at the weekend and thought it was worth investigating... as normal I have found a PL-259 connector soldered in the most appalling way possible - I suspect this may be the culprit so it has been duly replaced.

Whilst I was doing this I decided to draw a diagram of what is connected to what -  was getting in a bit of a muddle, so here it is:

So at least I have a known reference point to look back at now.

Not very exiting, is it?

Hows the Interfacing?

Well,

Following my acquisition of an FT-450 to take on my travels, I've been making a digital modes interface for the radio today; I ended up with this design (like 0/10 for originality!):

I've built the electronics into a small plastic enclosure that I had here and eventually I've got it working 100%.

I struggled with FSK RTTY; it just didn't want to work for some reason. I tried re-making the switching circuit, tried swapping it for the (working) PTT switch - all attempts failed.

I then realised that I had never tried an FSK transmission from a PC using a USB to Serial adapter. Bingo! A quick search on the interweb soon revealed that my goal was in fact impossible! A bit more research on the MMTTY Yahoo! group revealed the fact that there is a software fix for this - it's called EXTFSK and is a dll that you drop into the same directory as the MMTTY exe file.

Bob is now my Uncle and all is working well; tricky though - may never have found that and was close to giving up!

Cat's as impressed as normal:

Good though, egh?