I used to use a 40 watt incandescent bulb with my old novice 6146 crystal oscillator, that can work.
Though be aware of this statement? "Tungsten-filament incandescent lamps exhibit a very-high positive
temperature coefficient of resistance with the cold filament resistance being approximately 10% of the hot filament resistance."?
from:??
So the load that the lamp presents will vary drastically with power, you can't just measure the filament with an ohmmeter.
I think you are better off? spending $0.10 each on some Xicon 3W 200 ohm resistors, item?283-200-RC?from Mouser,
four of those in parallel give you a 50 ohm load that can dissipate 12 Watts.
Then inspect the RF voltage across that load using a diode RF probe and your Harbor Freight DVM.
Jerry, KE7ER
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On Fri, Jun 15, 2018 at 12:40 pm, Ralph Mowery wrote:
It is tough to do much with some test equipment.? Everyone should have some kind of way to check the SWR at a minimum and that can be used as a rough guess as to the output.? Been in that shape many years ago.
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To see if you have any output you can use the time honored way of a light bulb.?
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For the ubitx you can use the small bulbs such as the tail light of a car.? I tried it just to see if it would work.? Depending on how much output you have it will light up the bulb somewhat, usually much less than the nominal 12 volt of a car.? Do not do this test very long, just a few seconds to see if the bulb will light.
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The ubitx will probably blow the older # 47 and 2 D cell flashlight bulbs??
I am not sure if it would light one of the 5 to 10 watt 120 volt bulbs or not.
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Just make sure it is a filament bulb and not one of the newer LED types.
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