[Amps] Good engineering

[Jim Thomson]

ORIGINAL MESSAGE:

On Mon, 22 Mar 2010 19:31:09 -0700, "Jim Thomson" <Jim.thom at telus.net>
wrote:

>
>##  I wouldn't be holding Command or anybody else up as any kind of 
>'standard of engineering excellence.'  If these ham amps  were built right,
>they would all have individual, adjustable bias  for each tube, plus mating
>metering, real bandswitch's and real tank coils, and plate xfmrs... and maybe 
>toss in a real tube..... and not something with a floozy 4 watt delicate grid.

REPLY:

Any fool can overbuild a product. Good engineers know when to stop,
and good engineers get paid good money to get it right.

73, Bill W6WRT
##  Bill , got any idea what 3 x NEW  EIMAC  3CPX-800A7's  cost these days? ##That's the tube line up used in the HF-2500E.. really smart.  The 12 ga wireroller inductor,used in the 10 kw palstar ant tuner is a joke, along with SO-239's,and the mickey mouse balun on the INPUT of the tuner.. which will explode. Toss in undersized tank coils, bandswitch's, mickey mouse tune/load  padding schemes,t/r relays that hot switch, and you wonder why the HB amp builder gets into designingand building his own stuff.  Ten tec brags abt the 3.5 kva CCS  xfmr used in the centurion,and sez it's good for 7 kw.."IVS"  [int voice service], yet it barely does 1.3 kw pep out....[almost legal limit].  A buddy accidently had his cat fall asleep on his footswitch for 2 hrs.His 87-A  was pumping out a 1.5 kw FM cxr on 29.650 mhz.   He had the optional cooling fan.The RF deck had turned into molten glop !  Alpha tech tells him..... " don't believe the hype"The home builder has the luxury of using what ever components he wants.. and can get hishands on.  Typ ham amps have cut every corner there is.  1/4"-3/8"-1/2" cu tubing is cheapat home depot... so why melt airdux ?  Ceramic vac caps are readily available, so I use em  fortune and load.  If something is marginal... I re-design it.   Who's the fool ?  later... Jim   VE7RF