High-Precision Nobsound 8-Pin Dual Bias Current Probes Tester for EL34 KT88 6L6 🧪 6V6 6550 Vacuum Tube Amp Amplifier - 2 Meter + 2CT1-C - Cathode Current Measurement Review

Does quick offset work, would highly recommend this time saver. Have already made a Marshall Haze40 and it was so easy. The counter arrived very well packed in a cardboard box and surrounded by foam. If this double counter was a little cheaper, I would buy two more.

After struggling with the multimeter I finally ordered it and couldn't be happier. No more fiddling with cables, analogue measuring devices clearly show you the current value and where you want to go! It is much easier to gain bias this way. It's so nice to see both tubes on this model to help balance the circuit, I can't tell you how much it helped.

The first one worked for several days. A few days later I went to check the bias and the cathode resistor on one of my EL34s burned to the ground as soon as I turned it on. I exchanged it and the same thing happened the first time I used it. The resistance lit up with a bright flash and a puff of smoke. This item is not worth the risk.

Obviously this device is relatively inexpensive. It wouldn't help if I were an FT amp repair shop though, but it works fine for my personal tube amps. It seems a little fragile but with careful use, handling and storage it should be sufficient for all my needs. The actual meters are fairly accurate compared to my Fluke 87 (a deviation of 0.5mA at around 40mA). If you have a Marshall or other tube amp that allows you to adjust the offset for individual tubes (or sets of tubes), this should suit…

I have had a pair of wired octal connectors to set lamp bias for many years. They disappeared during a recent move and I replaced them with this gauge. WOW! Next thing I remember, a customer walked in with a 4/40w Blackstar switchable amp that had failed and the output tubes were smoking. I soon discovered that all maintenance records for these amps were closely guarded at the Blackstar facility. So we started troubleshooting and traced the circuits to see what went wrong. The amps use a FET to