** The main difference being that combiners are the norm with solid-state due to the practical limit of a few hundred watts per module. Also, for the same number of watts of RF out, due to more wast
** GFI breakers have a reputation for RF detection, so some ferrite beads and bypass caps may be needed. To pass NEC, the bypass caps must be 1400VDC-rated. If you want your station to be fully NEC-
**High-efficiency BC-type designs are not suitable for applications where linear operation over a range of frequencies is required. _______________________________________________ Amps mailing list
** Dr. Schmidt. Please explain why high-efficiency BC-type designs are suitable for applications where linear operation over a range of frequencies is required. Tnx _________________________________
** Why not replace it with a plain-vanilla circuit breaker? ** Does she use the hair-dryer whilst in the tub? cheers, J. _______________________________________________ Amps mailing list Amps@contes
** If he loved his wife, would the Ham amp be plugged-in in the bathroom? If I pulled that little stunt, the Ham amp and the Ham could easily wind up in the tub at the same time. ____________________
** Not linear is OK for SSB? The difference in S-units between an amplifier that 60% efficient and an amplifier that is 90% efficient - for the same power input - is 0.3 S-units, or 1.76db. _________
** So why would a Ham want a not-linear amplifier? ** The bandswitch in a SB-220 is not very ok with a 3800vdc anode supply. 3000v is close to the limit for a SB-220. If one needs more output it tak
** Dave -- Why not design a 90% efficient linear amplifier for the HF Ham bands, document the construction process, and show us how to on your Web site. ______________________________________________
** I have yet to hear a Ham station on SSB who is getting 90% efficiency from his/her linear amplifier. My SB-220 linear amplifier probably uses c. $1.20 worth of electricity per month. Going to 90%
** Regulation of the anode supply buys virtually nothing except bragging rights. The most critical potentials in an amplifier are filament-V and, for tetrodes and pentodes, screen-V. ________________
** Good question, Steve. There could be a problem with junction-C on higher-Joule transient-V suppressors for RF service. _______________________________________________ Amps mailing list Amps@conte
** The sticky wicket with Class-E for Ham applications could well be the requirement for wide frequency coverage. However, since some Hams already use electron-tube monobander amps, maybe they would
** I heard a rumour that the 3cx1200A7 is being phased out by the 3cx1200Z7. ** The 8877 grid is rated at 25w. If gold boils off the grid, it isn't from HF energy. ___________________________________
** Bill -- Mouser carries the fuses, but the problem wasn't caused by defective fuses. My guess is that you had a parasite at c. 120MHz, which caused a domino effect, which eventually blew the fuses
** For what I do -- i.e., 40m and 60m daytime conversations with a dispersed group, the best antenna is a dipole at 30'. The best amplifier is whatever it takes to be heard over the jamming. In such
** The weakness in the 3cx1200A7 is that it has twice as much feedback-C as an 8877. This problem was solved in the 3cx1200Z7. _______________________________________________ Amps mailing list Amps@
** My advise is: Send the tube to two rebuilding services. I have had the experience of having a good tube declared a dud so that the rebuilding service could make money either by recarburizing a tub
and will ** The "neutralizing" circuit in later production Al-1200s reportedly makes the tube more prone to oscillate at the AL-1200's VHF anode resonance than earlier models which do not have "neut
** Voltage ratings are not enough. A high-pot test to determine the actual avalanche potential is the bottom line. Amperage rating can be estimated fairly well from package size. ___________________