Hi Jerdy, is automotive polyurethane over mdd board, the front of the cabinet is veneer and automotive clear coat.
To be honest the caps idea was a design flaw
, This was the only way for the tubes to be higher 
12GT5
Today, I built up some boards for the MA-1 for 12GT5 Novar tubes and used 9 pieces of Keystone 1434 as each socket since PCB B9E are unobtanium...
I've also made a B9E breakout socket PCB since there are no B9E sockets available these days. I'll post about it in Vendors soon.
Today, I built up some boards for the MA-1 for 12GT5 Novar tubes and used 9 pieces of Keystone 1434 as each socket since PCB B9E are unobtanium...
I've also made a B9E breakout socket PCB since there are no B9E sockets available these days. I'll post about it in Vendors soon.
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This is an 807PPP that I'm in the process of finishing. It's playing on the bench through a set of test speakers atm. It's pretty quiet except for some mechanical hum from the toroid power transformer I mounted on the bottom cover for space reasons. It's using Hammond outputs and the large choke on top is also Hammond. The other transformer is for the 866AX filaments and came from a Motorola VHF transmitter. I'll some more photos when it is finished including the interior. Thanks for looking!
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866 tubes LOOK cool but I won't use them. I'm from NH... Karen Wetterhahn - Wikipedia. I know, I know. It's not exactly the same thing. But look at what happens to mercury in the environment (e.g. https://pubs.acs.org/doi/10.1021/acs.est.8b07180 and https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1266&context=water_rep among MANY others). It's ridiculous to continue to use them IMHO.
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Even though it's off topic in a photo thread, as a university graduate in chemistry I feel the need to correct your post.
The articles you mention are about a mercury containing organic compound, not metallic mercury.
This it not the same thing.
You don't put a ban on tablesalt because it contains chlorine (poisonous gas) and sodium (highly reactive metal which reacts violently with water)?
Ever heard of amalgams in tooth fillings? That's mercury right in your mouth.
Yes mercury is a bad thing under certain circumstances, but perfectly safe under others.
In the case of mercury rectifiers, you are dealing with metallic mercury, not organic.
It's sealed in a glass bottle. You can't get to it unless you break the glass (why would you do that?).
Mercury is a much misunderstood element
Open the Windows and clean up the mess.
The amount of Hg in a single tube is small but partially evaporated.
Inhaling low concentrations of elemental (metallic) mercury over a period of years (work environment) can give health issues.
A single incident (low level) shouldn't be a problem.
Collect droplets by sucking them up with a plastic syringe. Seal and dispose as chemical waste.
Or have a proper spill kit on hand in case one breaks? https://www.grainger.ca/en/product/SPILL-KIT-SMALL-MERCURY/p/SPKCSKSMMERK
Not cheap though.
Not cheap though.
Even though it's off topic in a photo thread, as a university graduate in chemistry I feel the need to correct your post.
The articles you mention are about a mercury containing organic compound, not metallic mercury.
This it not the same thing.
You don't put a ban on tablesalt because it contains chlorine (poisonous gas) and sodium (highly reactive metal which reacts violently with water)?
Ever heard of amalgams in tooth fillings? That's mercury right in your mouth.
Yes mercury is a bad thing under certain circumstances, but perfectly safe under others.
In the case of mercury rectifiers, you are dealing with metallic mercury, not organic.
It's sealed in a glass bottle. You can't get to it unless you break the glass (why would you do that?).
Mercury is a much misunderstood element
Methinks you didn't read the articles. Even metallic mercury such as in the 866s undergoes changes from physical and biological processes when released to the environment. I mean, where do you think methylmercury comes from in the first place? But I won't be swinging swords with you. Maybe this will help: Basic Information about Mercury | US EPA.
I agree. I have a couple dozen and have used them for years. Have never heard of anyone harmed while using them. Much ado about nothing.
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Never cheap BUT these supposedly NOS AND NIB.
2 X 866JR MARSHALL TUBE. HALF WAVE MERCURY VAPOR RECTIFIER. NOS/NIB. AI #ENA | eBay
2 X 866JR MARSHALL TUBE. HALF WAVE MERCURY VAPOR RECTIFIER. NOS/NIB. AI #ENA | eBay