Kenwood TS830s

[llonen]

This hybrid radio came in for what is a typical repair for these venerable vintage sets, band-changer control inter-coupler had parted company and left the building. I was going to machine a replacement but I found a supplier for suitable substitutes, anyways further inspection of the RF cage found a cracked snubber capacitor (10nf) a good inch in diameter. So I ordered replacements rated for 2KV the high voltage in this area is around 800 volts, seemed a reasonable compromise, other than the bad solder joints on the valve bases the repair was progressing nicely.

Well when the parts arrived they were like about a 1/4 inch in diameter, so I re ordered 3kv 10nf parts, when these turned up they are still substantially smaller than the original part. I will upload size comparison pictures later. The original part is 20 mm dia and the replacement parts are 10mm dia.

[CapLeaker]

Re: Kenwood TS830s

that's how it goes... same thing with electrolytic capacitors. stuff is getting smaller every year. Kenwoods are really known for that brown goo that gets conductive and corrosive over time. Scrape and clean as soon as you see it.

[llonen]

Re: Kenwood TS830s

Well this set seemingly is one of Kenwood's cleaner examples in terms of hot snot and brown goo not otherwise specified, with regards to the ceramic anti parasitic cap well looking through the suppliers I use it seems 10mm dia is about average for this value and rating. I did look for a 5kv alternative but was not able to source one, and while i appreciate 800 volts is not particularly high the part seemed a little on the small side.

Well the RF section is back together, the coupling made good, valves tested and the bases reworked, tuned up and tested into a 50 ohm (100watt, 10db) pass-through attenuator to a RF power meter The set is producing a good 100 watts CW, this is about right for this vintage. If anyone is particularly interested I might post some general pics before closing up the set