Do any of you know what the 110 VAC power consumption range is for any
of the older 100-percent-tube-type SSB/CW 100-200 watt class
transceivers?

I'm looking for the peak power consumption when transmitting CW.

Thanks...

Rick WA1RKT

wrote in message
...

Do any of you know what the 110 VAC power consumption range is for any
of the older 100-percent-tube-type SSB/CW 100-200 watt class
transceivers?

I'm looking for the peak power consumption when transmitting CW.

Thanks...

Rick WA1RKT

You maximum power consumption will be when you are transmitting - right?

DO the napkin rough math. P=IE ... this is still on the amateur exams --
or maybe the memorize the multiple choice answers is a popular approach.

200 watt RF transceiver. No conversion is 100%, for this exercise -
let's assume a 50% efficiency to RF output.
So that would require 400 watts of power -- at 110 VAC about 4 amps
plus other devices drawing current (usually less than 1 amp).

Less than your toaster in the kitchen.

gb

In message ,
writes

Do any of you know what the 110 VAC power consumption range is for any
of the older 100-percent-tube-type SSB/CW 100-200 watt class
transceivers?

I'm looking for the peak power consumption when transmitting CW.

Thanks...

Rick WA1RKT

Rick,

If it's any help, the spec for the National NCX-5 on a 117 or 234 volts
AC supply is 150 watts receive, 365 watts transmit, the TX is rated at
200 watts PEP input on SSB and 200 watts on CW. A Swan 350-C draws 250
watts average or 600 watts peak power, with input powers to the PA stage
of 520 watts PEP and 360 watts on CW (seems a bit low on AC wattage to
me, but that's what the book says). Both these transceivers have
external PSUs, either mains or 12 V DC. I have the specs on the Swan
500-C and Heathkit HW-101 if required.

73,
--
Roger Basford
(G3VKM)

On Sun, 7 Sep 2003 08:20:24 +0100, Roger Basford
wrote:

I have the specs on the Swan
500-C and Heathkit HW-101 if required.

Good morning, Roger.

No, that won't be necessary, the info you and others provided is more
than enough for my purposes.

Thanks much to you and the others for your help.

73,

Rick WA1RKT

It might take ten times the power to run a tube rig on idle as
solid state. I'm not sure of the real numbers but I'd guess 5
watts for my solid state ICOM and 50 watts for my SB-102.

Most manufactured solid-state rigs require 1-2 amps on receive - that's 12-24
watts.

I don't know what model ICOM you refer to but 5 watts at 12 volts is less than
half an amp.

The SB-102 requires 12 volts at 4.75 amps (or so) to light the heaters, 300
volts at about 100 mA B+, and some bias. Works out to 57 watts of heaters, 30
watts of B+ and maybe 3 watts of bias - say 90 watts total. Press the key and
you add 800 volts at 240 mils - about 280-290 watts total.

Remember, though, that the efficiency of the power supply has to be considered,
both in the solid-state and tube case. In the case of heater power, a
transformer is very efficent (90-95%). Unregulated DC from a typical SS suply
is almost as good - (80-90%). Regulated DC (typical series-pass-transistor SS
supply) can be much worse - down to 50% (worst case) when a big supply runs at
light load, because the pass transistor has to burn up a lot of volts.

So in the case of a tube rig that needs 90 watts from the power supply on
receive, the AC demand might be 110 watts. Compare that to an SS rig that needs
2 amps at 12 volts on receive but has a power supply with ~50% efficiency at
light load - total AC demand 90-100 watts. (This is why switching supplies are
so popular - they are very efficient).

If your primary power source is 12 volts, it's a whole different ball game
because the SS rig doesn't even need a power supply.

--

On transmit, my ICOM spins the fan and draws 20 amps at 12 volts,
240 watts. The SB-102 might take 300 watts.

Both are reasonable numbers, but note that often the "12 volts" is actually
more like 13.8.

The Elecraft K2/100 requires only 250-350 mA (depends on options) at nominal 12
volts on receive. I don't know of any full-feature rigs that draw less on rx.

73 de Jim, N2EY