Discussion in 'Amateur Radio Amplifiers' started by W1BR, Feb 2, 2018.
Was thinking of that as well
You need to go thru a background check to by pressure cooker parts now.
I think the waiting period is 5 days. I made that up just for grins.
I just made the no fly list and now have outstanding FISA wiretap warrants.
I got mine from the local power provider's transformer shop. I would be amazed if it contains PCBs.
Getting their yuuge fill pump to give ONLY a gallon was the only issue.
The boiling temp of ordinary mineral oil is 690 degrees F at 1 atmosphere.
The Heath Cantenna pressure relief was just a long 'Rivet' with a larger head setting on a gasket seal type washer.
Able to move about 1/8" and loose in it's hole..
It is not spill proof.
You can get these cans and tops at any Home Depot or LOWES store in the paint section.
All very interesting . . .
But I wonder why anybody actually NEEDS a Dummy Load that you can transmit into for long periods?!
I only have a 100W air cooled carbon resistor dummy Load . . . but it's fine giving it 1300 watts for a couple of seconds at a time . . .
Why do you need more than that?
Given that most of our Linear Amplifiers are designed for amateur SSB duty cycles, I only ever load up at full carrier power in short 2 second bursts anyway, to protect the amp.
If I really needed to test an amplifier at full power for long periods (for some reason that I can't think of) I'd just choose a quiet band and feed one of my antennas !
I can think of a few good reasons to have a Cantenna type load.
1. I'm not going to assume that a band is really dead or there is nobody on it with my crummy antenna.
2. Many of us build or repair amps and you may need to warm things up a bit in the process of tuning and testing it.
3. Tuning may have to take place on bands that are not dead or I don't have antenna for.
4. There's no way I'm going to try and stick several hundred watts plus into a 100 watt load, even for a few seconds. I'm a 'wussy' that way...
Well unless there's a Contest on, NO band is ever that busy that a single carrier is going to upset anyone.
Plus I've had my dummy load for 48 years . . . and it's still fine !