? The presumably highly-qualified and very experienced engineers at a well-respected West-coast amplifier manufacturer have managed to design three amplifiers which use 4.75 - 5.25 V rated filament
// All of my carbon comp resistors met the trash-pickup one Monday after I did some measurements with my Fluke DMM. RE reading specs: It is amazing that a number of Ham amplifiers use 500pF and 1000
yea, verily Tom Rauch (SB-1000) and Dick Ehrhorn (77SX) are experts -- and "experts" apparently don't need to read no stinkin' mfg's specs. Tom still maintains that the 3-500Z is rated at 550mA, not
[] Good advice. Mouser has 1M-ohm, 2W resistors that will apparently handle 1400WV and they are c. 30-cents each. Also, Vishay/Dale at http://www.vishay.com/products/resistors/main.html#fl has indiv
[] Does an owner of a Heath SB-1000 know the value/WV of this capacitor and on which band it is used as a padder? [] It is not being used within it's current rating. Also, it is a coupling/bypass ty
[] The 160m tank padders in the 77SX have high temperature drift and they are used above their current rating. cheers, Phil - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, www.vcnet.com/measure
Mica dielectric caps are good for 160m and 80m tank padders, however, opposite to barium titanate dielectric "doorknob" caps, mica cap's current-carrying ability decreases as freq. increases. Micas
A friend has a 77SX. He asked me what was the reason for the tank drift on 160m. The reason(s) turned out to be that the tank padders were being used above their stated current ratings and they were
[] 500pF 5kV doorkobs - such as the 58-series - are typically designed for bypass service, not tuned-circuit service. - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, www.vcnet.com/measures. end
5MHz is not the cutoff freq. It's the neighborhood where the dissipation factor in aluminum-silicates begins to increase. Mica works ok at 28MHz, but the current carrying ability is somewhat less th
to [] The problem is that the conductive medium begins to arc internally. This can be seen by observing the current-versus-voltage relationship. For example, a 10M, 2W carbon-comp resistor dissipate
The Mica transmitting capacitors in my junk box have decreased current ratings as freq increases. cheerz, Eric - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, www.vcnet.com/measures. end
Rating of 50-Series ceramic, 100pF, 7.5kV, n750: 1MHz--3.6A, 30MHz--9.6A http://www.highenergycorp.com/ceramic/ht50.html I said that the current carrying ability decreases above 5MHz. - R. L. Measur