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--- In ham_amplifiers@..., R L Measures <r@...> wrote:

Indeed, and it's all because of greed. . During the recent
heat wave in Southern California, transformers were popping like
popcorn in residential areas because Southern California Edison
originally cut costs by installing transformers that were Way too
small. For example, on our block, a 50kva transformer supplies
power to c. a 200kva max load. During one heat spell, the
transformer got so hot it broke a seam and started to leak coolant
oil. Edison's fix was to replace it with another 50kva unit.

### The BIGGEST pole mount xfmr is 100 KVA. When u see one up
close... they are huge.. and heavy..... and when u see 3 x 100 kva
xfmr's all on the same pole.... then realize the total weight is
imense.

## Anything bigger than 100 Kva.... then they put em on the
grnd... partially sunk into the grnd ..in a kiosk. Most grnd
mount xfmr's don't have oil. SOME do.... some have
recirculating external oil pipes. You see em at shopping malls,
etc.

## My electrical buddies were telling me how big the primary
fuses are on these pole pigs....you do the maths....most would
melt b4 any fuse ever blew.

### For a single phase RF deck that needs say 6900V @ 3A...

a bare minimum of 34 uf will provide barely 3% ripple.

A 100 uf filter will provide 1% ripple... and far better
DYNAMIC Regulation.

RICH SEZ...And nobody on the Rx-end can hear the difference, Jim.

### On ESSB, you sure can..... and if you want good ssb audio on
a yaesu MK-V...check out the 85 page Document W5CUL and myself
wrote. It's on and also
[under mods]

### Once you modify these xcvr's.... they sound like AM broadcast
stations.... I'd say a lot better.

### BTW... ut FT-1000-D is only flat on RX... up to get this...
900 hz... then it rolls off above that !

### On TX we feed the analog BM directly [via a jensen xfmr]
On RX, we tap off the analog ssb product detector... and take it
external. The DSP in the yaesu MK-V is joke. When u toggle
between the analog mode and dsp mode... there is a 20 db RISE in the
TX noise floor... with mic gain on zero. The built in yaesu mic
pre-amp adds another TON of noise.... worst mic pre-amp ever.

### The stock yaesu RX af circuitry... AFTER the analog ssb
product detector leaves a lot to be desired.

## IMO... why listen to bad ssb audio, when it's so easy to
improve it.

Later... Jim VE7RF







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