The amplifier units are full of valves, capacitors and resistors and with old age become unreliable. Effectively these items are still being expected to work 20 years after the expected end of useage!
|Original Spec capacitors|
All of the spare amplifiers that we recovered from scrap aircraft have now being used up and the ones in the aeroplane were starting to weaken with low and stagnant indications. Therefore it called for drastic action and 'The Brains Trust' got to work (namely Ken 'Radio' Sanderson) who came up with the up to date replacement specs for the capacitors. Some are no longer available down to the absolute identical spec but, we've found every type to replace them. There are 9 in each amplifier and much 'soldering & burnt fingers' has resulted in a batch of 6 out of 7 repaired ones now working, There are more to do now the formula has been set! The next job is to fine-tune them with the fuel gauge test set before they are fitted back into XL231.
|Original spec capacitors|