Just bought a second hand Code master CWR-610E telereader, which can decode rtty (and CW) and display it on a compositie video screen. Amazingly for a early 80’s device it worked perfectly.
I do had to do some adjustements, but they were all outlined in the excellent manual.
The first thing I did was changing the video output to composite instead of RF. This meant changing the following things:
Changing method when using video monitor TV instead of home TV (RF)
Changing from RF OUT to VIDEO OUT
Cut and bridge with solder at two positions:
1. RF OUT selector part: Cut "R" - short "V".
2. RF converter part: Cut "RF -VIO".
Cut and short correctly by referring to the parts layout chart.
VIDEO OUT specification
Composite video signals (video normal modulation, synchronous negative modulation, 1.0 ± 0.2 Vp-p, 75 ohms).This gave a beautiful, steady image on the small b/w monitor I have:
Next: getting signal into it.
Since my transceiver isn’t connected yet, I connected my smartphone’s output and lo and behold, the signal came trough, but was gibberish.
After some research, I found out that the weather rtty I was trying to decode, was in reverse coding, so I had to set that up.
That involved cutting a trace on the board:
The input of Baudot and ASCII is set at mark L at the time of shipping. It can be changed to mark H.
Cut the MODE SEL REV [cut land REV].
After that and setting the baudot rate to 50bps it worked!
Once my transceiver is set up, I will try and make it better and make some RTTY QSO’s.
Next time I will try to add a switch to switch between normal and reverse.