Sir Andy . . . . .

After initially “really searching” your specified “michigan mighty qrp transmitter “ it is revealing to be but a mere 12 Volt powered transistor “peanut whistle” and not encroaching upon the tube powered behemoths incorporating kilovolts of plate supply voltage .

Usually those styles of ear mounted postage stamp micas were rated upwards of 500 VDC and on upwards for transmitter use.

In your situation, merely ohm it out on your highest available ohms scale.

OR if you want a more subjective dynamic testing, use your 12 DC supply or (2) 9 V rectangular “transistor radio batteries” plugged together in series

One end of a clip lead goes to the free POSITIVE term end of the “battery” with the other end of that clip lead going to one ear of the mica capacitor.

One lead of ANOTHER clip lead goes to the NEGATIVE term end of the “battery” with the other end of that clip lead going to the NEGATIVE metering lead.

The POSITIVE metering lead is then touched to the free ear of the mica capacitor.

Then you switch the metering range on downscale to its lowest range, any reading that eventually doesn’t drop on down and stays at a level is indicative of DC leakage . . . . and reason for rejection.

To even FURTHER evaluate that cap capability at higher voltages, think of any piece of tube equipment that you have, such that you would have hundreds of DC volts available from a similar clipping in and borrowing from its power supply output.

This time you insert a 1 meg current limiting resistor in series with the test lead that taps off the B+ from the “donor” supply, then proceed with the prior test in the same manner.

( This time you keep one hand in your pocket . . . if being in a touchy metering situation)

This modified procedure then lets you find the exact capability of that capacitor, yet, in a non destructive test mode.

Notice:

I n the higher voltage testing and with the intermediate capacitance value you specify, you may be

w. . . . .a. . . . .i. . . . .t. . . . . i . . . . . n. . . . . g for an initial charging surge voltage of the capacitor to gradually /and/ eventually dissipate on down to the REAL leakage value . . . IF there is any leakage even being existent.

A speedy work around solution is to just manipulate your wired “contraption” around, until you can short the + & - meter leads to each other. That immediately fully charges the capacitor and if the leads are then un-shorted, any voltage showing up from the just prior ZERO volts is being DC leakage.

73's de Edd

How Do They Get Deer To Cross The Road Only At Those Yellow Road Signs ?