Aspes, Spanish Valve Television
Another kind donation, a 19” valve TV, made by a Spanish company called Aspes. The company started in 1949 making and supplying household goods and in the 1960s, ventured into TV. This TV, I guess dates from the mid to late 1960s. The set would have cost over 17,000 pts, which would he been a fortune in those days.
Before getting too involved, I checked the CRT and the meter showed it had good emission and cut-off. The muti- section smoothing capacitor was reformed for a few hours until it showed it was useable. We don’t like those blowing up and emptying the contents of their stomachs everywhere.
With current limiting in place, the power was slowly applied and left at 50%, 110V for an hour. Some crackling from the loudspeaker could be heard, so that was a good sign. After bringing the set to 80% power, we had a bright line across the screen which meant we had a total frame collapse. The frame output valve was running hot which suggested the pentode section was drawing current. There was indeed HT at the Anode of the ECL805, but no frame sawtooth ramp. Then, a hum and the current limiter tripped. My first worry was that the power transformer may have failed. The 4 diodes in the bridge read okay, but at one of the tabs on the multi-section smoothing capacitor read short circuit to ground. Unfortunately, I have no data on the TV, so back to basics and fault finding. The short was traced to a 0.1uF 400v decoupling capacitor. With that removed and replaced, we were now back to our white line collapse. Scoping around the board did show a sawtooth waveform. But at pin 1, anode, of the ECL805 triode section, there was no sign of any HT. Expecting to find more short circuit capacitors, I was wrong. Tracing the circuit out, I found a 220K Ohm anode load resistor which seemed to take its supply from the boost HT rail from the line stage. This was open circuit. Replaced it and checked for shorts. Powered up and we had a full raster. Great! With a pattern generator connected, it seemed that the line frequency was way out and the picture, whilst sync locked, was X 2. This was due to an open circuit line hold control. Cleaned and adjusted, we now had a great image.
Very pleased with the work, strong CRT and as usual, solid audio. Nice old school TV, only transistors being in the UHF and VHF tuners. All the rest, valves throughout.
