Analog Panel meter holes sizes

[Opcom]

Analog panel meters with round bodies require certain hole sizes. Usually if a meter body fits in a hole it didn't originally come in, it fits well. Lucky for us, until we have to add more meters.

These holes are not usually basic sizes, such as 2" or 3". I measured some meters bodies and they were 2 1/8", others 2 1/2", etc.

Looking at two typical meters:

'marketing' meter size # actual bezel diameter # body diameter # bolt ring dia. (3-hole)

2.5" # 2.7" # 2.18" # 2.44"

3.5" # 3.5" # 2.5 # 3.16"

There's also the size of the small R390 type meter, and I think one other common size body that is closer to 3".

Is there a known chart or list of common meter panel hole sizes for analog meters? I have to borrow some punches and sure would like to punch the meter holes for several projects at once. Easy with rack construction to punch several panels for meters.

Also does anyone know what transmitter the top row of meters in the picture are from?

[N1BCG]

What an amazing meter collection!

The transmitter that came right to mind is the RCA BTA-1R:

[Opcom]

What impressed me was the 5 Amp scales on some. wow. I have most of those. When Nortex closed I got the meters. They are stashed in a barn in Gainesville TX. Among other fun things.

[KB5MD]

Those meters should have an RCA logo at the top if they are from a BTA 1R1 or at least the ones I've seen do.

[W4RFM]

I agree these "should" be from an RCA. However I have salvaged some meters like these from RCA equipment that did not have the RCA meatball on the face.  They might have been made when Westinghouse and RCA changed their meter agreement, back when. I would also bet they are from a RCA box.

[N1BCG]

What impressed me was the 5 Amp scales on some.

Indeed, and it looks like that meter on the end says "Direct Current". A 0-5A meter for "Radio Frequency" would be a bit on the low side. The Gates BC1-G (1kW) has a 0-8A meter for antenna current. A 0-3A meter would be perfect for amateur use where 200 Watts would show 2A and full scale is 450 Watts @ 50Z.

The RF ammeters on the transmitters usually remained in circuit whereas meters at the tower bases were usually shunted out of line unless being read.

[Opcom]

Those are DC meters. Plate current? I'd guess they would have normally read half scale or so but don't know.

There are a couple of 1940-1950 vintage 15A thermocouple type RF ammeters here and a big brass 5A one with a scale of 5000A about 6" diameter. No clue what it is from.

Didn't someone say that old TC meters from BC rigs are good only to a few Mhz?