While exchanging tall tales at the bar at the RSGB HF Convention over the weekend the discussion came round to the need for an amplifier specifically optimised for solo DXpedition use. The holy grail
The lightest weight power supply would likely be a voltage-multiplier type operating direct from the electric mains. With a x6 V multiplier and 230V mains, c. 1600vdc could be produced for c, 1kg in
Author: Ian White, G3SEK" <g3sek@ifwtech.co.uk (Ian White, G3SEK)
Date: Mon, 14 Oct 2002 22:30:39 +0100
Take a look at www.uksmg.org and find your way to G3WOS's description of his 8877 DXpedition amp for 6m that fits into a pilot's carry-on case - complete with 115/230V mains supply. If he can manage
I don't believe a 1 kg power supply using a 6x multiplier at 50 Hz or 60 Hz is possible, at the current level required. Unless someone invents nearly zero-mass large-value capacitors required by the
Well, I've built a 500W 50MHz amplifier, which weighs in at a little over 8KGs all included. It's MOSFET (16 x low-cost IRF510s!), and has a switching PS (bought very cheaply as surplus). IMD is bett
Hz nearly a power Many years ago there was a design in a UK magazine using 3 x 4CX250s with voltage quadrupling off 240V mains - arranged to give +/- 700V so as to minimise the voltage offset to grou
** I don't know how to go about calculating the ripple or how to size the capacitors for a quadrupler ps. My estimate of 8 caps per quadrupler assumed that some seriesing and paralleling will be nee
I think you mean the SB200/201. There is also the 2x572 Heathkit amp whose model number I don't recall that was intended for mobile use and does not have a built-in PS. These are available cheaply an
Vic, I think he meant SB230. It's about same size as SB200 but lighter and used a single conduction-cooled tube (8873 I think-?) with internal AC PS. -WB2WIK/6 "If everything seems under control, you
<PRE>In my opinion the future for lightweight SSB amplifiers would be a solid-state amplifier based on EER ( Envelope Elimination and Recovery) with a Switching Power Supply. An EER amplifier can use
Right, I saw '230' and for some reason (age, probably), read '220'. It is possibly lighter than the 200. On the other hand, those tubes are hard to find. Vic K2VCO
No, and efficiency and weight can be helped further by running at higher DC voltages using off-line buck style converters. I have run class E cw at 46Mhz using 100V off of a buck converter for 300W
The lightest package for 500W out will be an amp with a pair of EL519/PL519 which will do 600W easily. Power supply transformerless with voltage doubler / tripler can be made quite variable for mains
The small dual 572B Heath amp was a mobile version of the SB-200. Very very small, it was called the HA-14 and had outboard AC and DC power supplies available. Pretty rare unit in clean condition. 73
Although Steve doesn't believe it, a Pspice simulation suggests that a 6X multiplier using "just enough" 470uF 385v capacitors to keep within their voltage rating (15 in all) and 240v/50Hz mains giv
Steve's 0-volt prediction sounds a tad fishy. Would it be possible to put two quadruplers in series if they were powered by the same source? - Rich..., 805.386.3734, www.vcnet.com/measures.