Item Description
This is a UK made AVO MK4 vacuum tube tester.
This is the AVO MK4 vacuum tube tester from Europe.
This is said to be the most highly rated (overseas forum) of the late model MK series.
110 V specification with FUSE switching.
The compact step-up transformer modified by the Kuro'ya operates at 100 V of the Japanese power supply.
The ultimate tester for more than 7,000 types of vacuum tubes (Not compatible with Japanese balls)
It is theoretically possible to measure any sphere as long as it can be attached to the socket.
There are a lot of rust stains and scratches, but it works properly after being maintained at a dew shop.
I'm sorry if I'm wrong about the explanation of Kyuroya.
This product was used by a European owner.
I think I was using it while fixing it, because the movement of the meter is very light.
While I was removing dust from the inside of the glass, I found that the white paint on the inside, which is also the kimon, had been wiped clean.
It is known that it gets crunchy over time and breaks the meter.
The early model AVO sold before became heavy as the powder got into the meter.
We sold it as a junk product because it was not accurate.
This product may have been repaired or overhauled because the meter works too lightly.
The zero point adjustment screw doesn't work, but zero is correct.
Please use it as it is (Don't touch me.).
There is a compatible meter available in the UK, but it costs 500 euros.
It will cost more than 60,000 yen before it reaches you.
It is also a possible tester.
The circuit is simple, so I think it is easy to maintain if you are familiar with it.
The circuit structure is completely different from the vacuum tube tester made in the United States.
Maintaining is said to be very easy. (It's impossible at the Gyuroya.)
Replacement of two electrolytic capacitors and improvement of the thumb wheel switch due to the sweetness of the solder.
We are doing maintenance at a Kuro shop.
At present, measurement operation of 6V6 6L6 6FQ7, ECC 189 and others have been confirmed.
----- NOTICE IN PARTICULAR -----
Enjoy the setting of this product, not a quick measuring device.
Each time we pay attention to the anode voltage and the screen voltage, we take time to measure one.
Enjoy the process procedure (play).
The operation is easy once you get used to it but there are many steps (That is fun.).
For example, if 6L6 is set as shown in the chart, 80 mA or more will flow to the anode.
A full swing is fine, but I want to enjoy it slowly, so I drop the anode voltage from 350 V to 250 V, set the screen voltage at 250 V to 225 V, and measure it at around 50 mA.
I'm sorry for preaching to Buddha if you are skilled.
Please understand that this is the ultimate device for those who have the above skills to play while maintaining.
I don't know if it is perfect or not at all. You can understand that it is a junk product that works somehow.