[Amps] Price per Watt Conversation

[Jim Thomson]

Date: Sat, 22 Apr 2017 20:20:30 -0400
From: "Roger (K8RI)" <k8ri at rogerhalstead.com>
To: amps at contesting.com
Subject: Re: [Amps] Price per Watt Conversation

There was such a device listed on here just a few days ago, rated at 2KW 
"carrier" MAX for $250 ea. A pair running 1500 out would be very 
conservative.  It's a given that running them at max would result in 
short lifetimes, but a pair at 1500 should last a very long time and at 
a cost comparable, even better compared to conservatively rated, 
imported tube amps at 1500 out.

Found it: 
http://www.richardsonrfpd.com/Pages/Product-Details.aspx?productId=1241241

Browser history can be handy at times.

73, Roger (K8RI)

##  Ok,  $250.00  EACH.   So what.   If 4 of em are used, the price tag of the
1.5 kw amp just rose from  say $7k  to $7.5K     In the bigger scheme of things,
that extra $500.00  is going to be money well spent. Pay once, cry once. 

## Leigh is correct, when they say CW....they mean dead cxr.... and not keyed CW. 
On any of these  SS xcvrs  currently being produced, they all draw normal idle current
when used in keyed  CW mode...and ditto with SS xcvrs  no longer in production. 
IF they were biased into deep class C, they would only be useful in FM mode.  On CW,
they would no doubt create key clicks. 

##  How far apart can each device in a paralleled  pair be....and still function in the RF environment ? 
IE:    IF they have to be packed tight together, heat will still be an issue..if the pair of devices are just
inches apart. 

##   I noticed on these  SS switches, used to turn on + off  AC power, like the large types, rated at 
20-80 amps CCS,  used in both single and 3 phase power, they required  SEPARATE massive
.25 inch thick aluminum plates for EACH device.  Some were 12 x 12 inch x .25   A lot of em are
bigger still.  And they dont mean a single 12 x 24 plate, with 2 x devices, with just 2 inches 
separation between them.   One of the examples they used was a 150 HP electric motor, running 
on  600 vac 3 phase, and 60 hz.   The devices could be paralleled for more current, and series 
for more V.     They had also factored in the start up current, with a loaded 150 hp motor, which
is typ triple the running current on some motors..and as much as 7 times the running current on 
other types of electric motors. 

## I used a simple contactor, less hassle, and no heat sink required, but im OT here. 

##  I forget what the typ push pull  SS  amp does for harmonics.  I think it was high for
the even harmonics, like 24- 40 db..and very poor for the odd harmonics..like 12 db. 
Without the use of a diplexer, that is one helluva lot of power being reflected back by the
LP filter... reflected right back into the final pa section...further cooking the final pa..
degrading imd, etc, etc. 

Jim  VE7RF