HICKOK Caddy Pal 820.
The TV radioman at that time put it in a vacuum tube caddy and used it for repair.
Only the electrolytic capacitor is replaced, and other problems around the socket are being repaired.
The structure is like a millivolt meter, and a 12AU7 vacuum tube is used inside.
As you can see in the image, you can measure resistance, voltage, transistor, H-K leak and grid leak of vacuum tube and cathode ray tube (CET) (microampere).
It is a multi-tester with vacuum tube CRT tube leak measurement and transistor measurement.
Operates with 100V Japanese power supply.
Resistance measurement
Set the left range to NPN, set the right range to Ω, and use the right light blue knob to set the full scale to measure resistance.
Measure in the voltage range in the same way as voltage measurement.
I think the voltage measurement is accurate.
Unlike modern passive testers, there is an error in the display because the internal resistance is different when measuring through a vacuum tube.
It corresponds to the voltage of the service manual of the vacuum tube equipment at that time and can be read directly.
Modern testers display high voltage due to impedance.
Vacuum tube leak measurement Measurement Vacuum tube heater voltage is in the left range
I will match it with.
Set the meter zero with the left light blue knob.
Check the mounting socket from the chart and mount the vacuum tube.
See leaks in the H-K range and X1UA range.
If the current is 3uA or less, it is normal that there is no leakage.
Transistor measurement and CRT measurement are not performed.
The test lead jack was the one at that time and the pin diameter
Is a special thing of about 3mm.
It is loose because there is no stock of 3mm class banana plugs, but I confirmed the operation with a general-purpose tester stick.
It is necessary to prepare a pin plug of about 3 mm.
I'm not sure if it's perfect.
You can understand that it is a junk item that has no fatal damage or defects.
------please note------
This product is not a dedicated vacuum tube test machine.
A normal vacuum tube that measures leak current with high sensitivity has almost no touch on the meter.
Since it is only a leak test, it is a very modest measurement.
It does not measure emission current, etc.
If you want to measure a vacuum tube, please consider a dedicated vacuum tube tester.
Please understand that this product is a universal tester of the time as a collector's item in very good condition.
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Even in the local United States, the finest products are already scarce and difficult to obtain.
The thing to introduce is the main body in the image,
It will be a manual and a copy CD.