Hi Chuck,
We've pretty much veered off from ten tec gear so I'll sign off by
saying that I think at this point, the problem with a marketable s.s.
ham amp is that several areas in the design start getting expensive
above 1 kw. The PA transistors are still fairly pricey, but also
because of the power (and perhaps the spectral purity requirement) you
need a relatively high d.c. voltage from the p.s. (48 v. usually I
think) and a lot of current so the p.s. gets pretty expensive. I
think you also need separate QRO bandpass filtering on the antenna
side (8 bands, 9 if six m.) so the combination of power and the need
for operation from 160 to 10 m. makes the filtering/combining/ant.
tuning costly on the antenna side of the PA. There was an outfit at
dayton this year with an operating legal limit s.s. amp that looked
like a beauty but I think they wanted a nice piece of change for it.
The company's name was Dishtronix I think. Anyway, tube amps remain
a lot cheaper in watt/dollar terms and in the ham market price is more
important than electric service expense and mean-time to failure
maintenance costs as hams aren't broadcasting (well, most hams aren't
hi hi).
I've heard that the s.s. broadcast rigs have become very
reliable--what problems there are seem to be mostly in the power
supplies. Harris is selling 200 kw to 2 mw s.s. rigs now.
http://www.broadcast.harris.com/product_portfolio/product_details.asp?sku=WWWDX200AM
http://www.rwonline.com/reference-room/special-report/2006.03.29-05_a_rwf_yingst.shtml
73,
rob / k5uj
<<<Hi Rob,
Absolutely, they are getting few and fewer. And no doubt the SS rigs are the
best way to go. I keep waiting for the SS amateur amps to get in line price
wise. I really feel we are at the point where a good SS HF amp could be
built as cheap or cheaper than a tube rig...Power tubes have gotten so very
expensive.The manufactors of amateur HF amps act like it costs a small
fortune to build a 2000 watt SS box.
73'
Chuck
W6RD>>>
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