Hi John, Don't thank me... it was a reply from someone who posted the information to my forwarding of your request over to the yahoo rfamplifiers group.
More than one person also mentioned the preferred use of Kapton (sheeting) as an option. I even found a source for the sheeting but it like many other things can get expensive. We had a number of the 1/4kw dual tube pa stations come into the old San Francisco Motorola Service Station (rip). They were very popular with the paging folks and some Government Agencies of course using carrier squelch radios. Since the 4cx250b PA's require a serious bit of care and feeding they always seemed to fail after a relatively short length of time. So there was many a case where the PA failed, the drive power was routed direct to the Antenna and no-one seemed to notice the difference in signal strength. When they worked.... wow... but when they fail... oh-no. :-) Much better long term performance was obtained with the dual 8560as pa's, which replaced the 4cx250b versions. The single 4cx250b pa's seemed to be fairly reliable... Nothing like a monster signal when you're not paying the electric bill. cheers, skipp > "kf0m" <[EMAIL PROTECTED]> wrote: > > Skipp: Thanks for the antique stove tip. I had searched mica > insulator and just found transistor insulators. Mica sheets > arrived Friday, and I got the TX fired up today. The amp > appears to be very comfortable in the area of 200-250 Watt > output. I got it up to 300W at one point but it didn't seem to > like that as well. We always ran it at about 200W before > when it was in operation. > > Now I just need to schedule some help to load it in the pickup > and then take the 60 mile drive to the repeater site. > > John Lock > kf0m at arrl.net >
