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This is one of the projects on (well, currently under...) my bench. This example provides 13.8 V, 28 V, and 50 V at up to 60 A: http://w6pql.com/a_big_power_supply.htm
The commodity Meanwell-type supplies stack really well and are inexpensive.
On Mon, Oct 19, 2020 at 04:26 AM, Ashhar Farhan wrote:
More than market, is that what we would personally want? As I said, the hidden cost really is the power supply. A 200 watts power supply is expensive. A pair of IRF530s can easily give us 100 watts or nearabouts.
Yes, 100w is what the market wants. Because... It drives well the OM2500...
Il lun 19 ott 2020 10:26 AM Murray Wills (ZL2IQ) <murray@...
> ha scritto:
It sure would sell well.
The market likes 100 W output.
In large amplifiers, the price is typically two dollars per watt output.
If someone could come up with a 100 W output amplifier, separate cabinet, connects easily to a QRP rig for $200, I think it would sell pretty well
50 W at $100 would also sell pretty well.
I wonder how many want higher output. The same IRF510 pair with 25v on the drains can easily push out 40 watts. They will need beefier heatsinks.
The real is the power supply. At present a 7812 regulator can run the ubitx.
At 50 watts output, we are looking at 12v/10A or a 24v/5A supply. Will it be worth the investment to go for that? Power supply is the challenge.
I have looked at PC SMPSs. The ATX supply can provide this juice. However, it is noisy. The noise sidebands extend quite a bit. The other option is a laptop power unit, it supplies 65 watts at 19v, it can power upto 30 watts of RF output.
The real beast would be using the MRF101AN, it costs 20 dollars and puts out very low distortion 100 watts. It needs a 50v supply with 2.5Amps.
Sigh, can anyone here design an Arduino based smps for us all? Seriously.
Any plans for a higher output transceiver with filtering etc, 160-6 for example?
On Sun, Oct 18, 2020, 3:32 PM Ashhar Farhan <farhanbox@...> wrote:
I remember my first look at a factory built transceiver (otherwise, all the hams in my town had a rack full of valve equipment that often pushed out 40 watts of CW from an 807)...
Saad Ali, President of FARSI (india's equivalent of ARRL) was visiting town and he was carrying an Atlas. We strung up a dipole at a hotel's roof and he walked in with just a small bag. The grossly misnamed 'Atlas' turned out to be a box slightly smaller than a shoebox. he switched it on and just kept working station after station. No PA Load/Tuning, no preselector, no valves. Just tune and talk!
I had to inkling of however in the world I would be able to afford anything like that. My most prized possessions were two JFETs, a 12v transistor radio power supply and a rusty iron. Looking back at the ubitx sitting on my desk, I still think I am almost there. TheAtlas-210x had 100 watts output, it had AGC, it had a punchy receiver from an all analog circuitry and a free running VFO that was bandswitched!
Following the discussion about having equipment affordable by a new young ham starting the hobby, I looked back at what I paid when I first got on the air in 1964:
$59.95 Knight-Kit R-55A Receiver (6 months before getting licensed, might have been a Christmas Present)
$10.95 Knight-Kit crystal calibrator option for the R-55A, so I could get within 1kHz of a correct frequency!
$49.95 Knight-Kit T-60 Transmitter (ordered the day my license arrived, 60w input and 20-30w output)
$120.85 Total cost spent as I already had a microphone, headphones, wire for an antenna from being a SWL
Equivalent today: $1,014.67 or about the price range of an IC-7300 station and needed extras
But, look at the current uBitX V6 for $200 that comes with all but a power supply and antenna for $200, that would have been only $24 in 1964! These wonderful radios knock down a lot of barriers to entry for the hobby! Oh what I would have given to have one of these back then...