and Restoration of a T1509 Transmitter part 4. 31st December 2005
next visit was on December 31st 2005, when I was joined by Ant, 2E0IFJ
and his mega super digital camera. Trying not to be distracted by
the regular flashes I spent the morning generally going over the main
transmitter unit checking components and wiring, sorting out the
mechanical bits etc.
< Here is yours truly delving about in the innards. I only wear a wooly hat when it is below freezing!
|< The decomposed bias supply electrolytic capacitors referred to on page 2 were replaced with modern 47uF 250 volt units and a new clip fabricated to hold them properly. The selenium rectifier shown here was also replaced with a silicon bridge even though it tested OK I wasn't prepared to trust it.|
< The roller coasters were coated with a blue substance which looked like ink and defied all attempts to remove it from one's fingers. Swarfega had no effect at all, neither did petrol or Vim. I just had to wait for it to wear off! Subsequent enquiries revealed that this was in fact a graphite grease used to protect equipment in storage.
The 'coasters were cleaned with a cloth soaked in Servisol and polished up to a shine.
< One of the PA tuning capacitors was seized solid so I removed it from the chassis (all nuts and bolts, no need to desolder anything). I discovered that the rotor bearings are adjustable, slackening them off and working a squirt of WD40 into them soon had the cap turning freely again. It was then possible to set the tension so that there was enough friction to hold the rotor at any setting but allow it to be adjusted smoothly.
|< Adjustment of the bearing tension.|
|< The PA chassis with the tuning cap removed.|
|< Looking out of the radio room door on December 31st. Even the Lightning had its wings tucked away!|
this transmitter to follow as restoration progresses...
We are looking for a presentable R1475 receiver to go with the transmitter to make up a complete station.
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