The Skanti TRP-6000 is a full-duplex HF-radio deployed in large quantities in the mid 1980-s on board of European sea-going fishing-vessels.
Specifications:
- RX: 100 Kc - 4.2 Mc
- TX: 1.5 Mc - 4.2 Mc
- Modes: AM, USB
- Power: 400 Watt
- Supply: 24 Volt, 28 Amp
The TX originally works on pre-programmed frequencies, stored in a ROM that is present in a DIL-socket behind the front-panel of the radio's upper- compartment.
I bought my Skanti TRP-6000 early 2005 out of a garage-sale, and found out that a few things were not OK:
- right utmost TX-display was not lit;
- hardly any output power;
The first problem was caused by a malfunctioning multiplexer TTL-IC. Repair costed me about 1US$ for a new IC. The lack of output power was caused by the fact that almost all potmeters in the RF-amplifier showed signs of corrosion. Some of them had completely lost their ruler...
It took me some time, but I managed to remove al pot meters without having to dismantle the assembly. After this, new pots were mounted and the TX functioned OK.
After all this, it took me a month to find out how the frequency-lock mechanism of the TX was implemented. For this I reverse-engineered the radio's internal control-EPROM.
By changing the software inside this EPROM, it was possible to unlock the TX so it could transmit on any frequency between 1.5 and 4.2 Mc. If You want to know how, just drop me a line ...
I had the manual and schematics scanned. These can now be found on http://bama.sbc.edu.