Meet Mr. Shockman
High Voltage Warning & Disclaimer
Tube amps can operate with lethal AC and DC voltages. All undertakings are always at the individual risks of the person working on equipment. I, as a personal, non-profit, pro-bono website, by the information I share, bear no responsibility for any such damages incurred by anyone. This is my digital Tube Amp diary, and by the fact that it is free, contains a great amount of useful practical information about Tube Amps and Electrical Measurements and Troubleshooting. If you want to get into working on hazardous equipment, you should take courses on electronics and safety, what I present in my website is not impled to prepare anyone, it is simply for orientation for interested parties to take formal personal measures for safety.
FOR ACCURATE INFORMATION ON SAFETY AND ALL SAFETY RELATED TOPICS, PLEASE VISIT THE OSHA WEBSITE
"Clever people fix problems
Wise people avoid problems"
WorkBench Safety & Good Practices
Safety protocols apply to a workbench, any field work or any electrical system.
Learn to NEVER use both hands on or near any energized equipment to measure voltages or currents. Always follow the one hand rule.
Also, always discharge power supply capacitors if working on a piece of equipment, to avoid possible nasty, biting DC discharge shocks.
Sometimes a DC discharge shock can pass enough milliamperes of current through a human Heart and bye bye, or get first aid and live.
Never deliberately work on energized equipment. Forgetting to turn somthing off when working on it often leads to nasty shocks.
Life is already hazardous; Tailgaters, Road Rage, Accidents, Weather, so why add risk?
Never touch any unknown metal electrical panel, until you measure the potential to ground with a DC/AC meter.
Always take both measurements, DC and AC, as the Law of Superposition can strike at any time, in a bad way.
You see, any electrically energized system can have, simultaneously on the same wire, chassis or terminal, both AC and DC on the same surface (wire, post, PC Board) at the same time.
So to accurately measure things like Power dissipation, you need to calculate for both AC & DC Voltage/Current dissipation then add both the AC and DC Power Dissipations together Pac + Pdc, for the total dissipation in Ptot Watts .
I highly recommend that you always have a simple but effective AC/DC Voltmeter handy in your GloveBox, Purse, Backpack, etc.
AMAZON sells the ASTRO-AI meter for $12.99 ea. priced to order at least one for the home and one for every Car Glove Box.
You never know when a Car Battery will die, they can sometimes give you hints, when electrical systems on the Car behave strangely.
All Batteries seem to die at the most inappropiate time. You can also use it to test D, C, A, AA, AAA Bateries.
The short and skinny on small DC batteries, if the nominal voltage is 1.5VDC you are good.
A fresh one will have a voltage of 1.6 to 1.7V for a new good battery.
If a 1.5VDC battery reads less than 1.5 VDC, such as 1.4vdc, 1.3vdc, 1.2vdc..... it's on the way out.
Also change Batteries at least 2x twice a year to be safe, or every year as a minimum. Note that some batteries will leak acid, so if you aren't using the remote, take out the batteries, save the remote.
Safely measuring electricity
The safe way to take any electrical measurements is to prepare, like throwing a Dart at a Dartboard, you have to concentrate.
Being careless, especially if working with energized circuits of any kind, think first.
A safe way to measure voltages when troubleshooting or testing is to always dedicate and connect the NEGATIVE terminal on the Metering Device to DC Ground.
This is usually best on the very first Power Supply Capacitor NEGATIVE connection terminal, or strip of you are lucky.
I prefer a strong DUAL ALLIGATOR CLIP wire is needed to firmly connect the NEGATIVE lead directly to DC Ground and the opposite end firmly to the DC METER PROBE.
It is best to have a work bench dedicated for these things. But I have worked on Hammond Organs on premises, on the floor, in dark musty Churches, and the work, although rewarding, is not much fun after you do it for awhile.
Also I prefer to make new stuff, than to fix stuff. But, I have become a good troubleshooter of electrical issues over the years. After all, I learned by working as a Technician for the first 5-8 years of my career with my Engineering Degree, then I went purely into an Engineering role once I was given the opportunity to work on Proposals and Design.
Setup for proper soldering iron(s), wire(s), and all of the nice to haves like a illuminated Magnifying Glass lamp, an anti-static bench mat, an Anti-Static Wrist Strap with a Button to the Anti Static Mat.
A nice long, fault protected AC power strip plus a slew of test equipment will make any bench worthy of respect.
If you can swing an anti static floor mat/rug, and finally Anti Static shoes, that would be great. But Anti-Static is mostly for the protection of Solid State, Tubes can take the discharges...
So this is the best overall basic setup. Then you just add a competent Tech (such as You after putting in the month's to learn this trade) and you are ready.
I like to have all of my tube testers out and ready, as I never know what kind of test I need on a particular day and time.
Remember the act of placing both hands on unknown metal surfaces, can potentially create a current path through your Heart, and only a few milliamps can be fatal and stop your Heart from beating properly.
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