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Anybody use switching power supplies?

Switching power supplies are reliable, but 30mv ripple is high. I prefer Astron linear power supplies with 8mv ripple. However, as a replacement in high power base CBs a switcher fits and cannot be beat.
 
GregT -

Do you run your two S700- 12s at 14.2 vdc in parallel ?? Mega Watt recommends 13.9 max when running in parallel. Does operating at 14.2vdc seem to work OK ?? If so, I will boost my voltage a bit

- J.J. 399
 
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GregT -

Do you run your two S700- 12s at 14.2 vdc in parallel ?? Mega Watt recommends 13.9 max when running in parallel. Does operating at 14.2vdc seem to work OK ?? If so, I will boost my voltage a bit

- J.J. 399
Well, I think he changed the PSUs. The single 700 I have is an older one and I can get 15.xv out of it. The two I have ganged max out at 14.2v. But, I had an issue with these when I first put them into use. He told me they were all set, just parallel them and they will do the rest. This was not the case. I put a clamp-on meter on each lead while transmitting and one PSU was delivering 40+ Amps while the other was doling out about 22 or so. So, instead of using caps and diodes, I just used two short HD jumpers to parallel the two, then connected my positive load on one PSU and the negative on the other. They pull evenly now and work flawlessly on 14.2v. When the amp is drawing about 62 Amps, the voltage drops to about 13.9v
 
I prefer the heavy ones with a big transformer. I had an Astron 35a supply that was pretty darn heavy, and powered just about everything for 10+ years, but lost it in a divorce. Another older one, that I kept at work (divorce proof), was a Kenwood PS-30, which is still in use today, and still powering my Kenwood TS-50. The last PS I bought (I hope) is Yaesu's FP1030A, and it's been running radios since 2018. As far as solid-state switching power supplies, I bought one from Alinco that let out the magic smoke in a record time of 2 months, and when it was working, it was pretty noisy (electrical noise on every frequency). My only other experience with solid-stated switching supplies is an oldie but a goody: Yaesu's FP-757GX. It's about 2" high and takes up the same amount of space that the 757GX radio does (designed that way so the rig could sit on top of it). It doesn't create any noise or birdies on the 757, and the two have been in use since '84.
 

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  • dxBot:
    Greg T has left the room.
  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
    +1
  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods