the NEW MXL Royer mod thread...

[???????]

you could search through nine pages, or I could just tell you again:

Hammond 1590E from Antique Electronics Supply www.tubesandmore.com $19.99

[honkyjonk]

Ah, thanks again Brad. What sort of tool did you use for the Power cord receptacle?

[???????]

a dremel and a very foul mouth. If I had to do it all over again, I would've drilled a 3/4" hole and filed it forever until the receptacle fit.

[wilder]

For those placing a Mouser order and wanting a chassis mount power transformer, I found this one:

http://www.mouser.com/search/productdet ... 553-01E07K

[???????]

good find!

[phantom power]

How do I know which wire from the tube goes to what # on the pcb? How are the tube wires numbered?

-AE

[phantom power]

Nevermind.

Just found a pinout diagram. For anyone else wondering, it's just clockwise. At least for the 5840.

-AE

[PeterSawatzky]

Well, I just finished my tube mic. I used the pre-made PCBs, but it doesn't pass any audio. I'm getting 38V on the filament supply and 107V on the B+. Please help!

[hulahalau]

Ah, thanks again Brad. What sort of tool did you use for the Power cord receptacle?

An alternative suggestion:

1. Instead of IEC power cord receptacle, use a Neutrik "Powercon" chassis receptacle and matching cord plug. There are two types , one for incoming AC power (the one you want), and another for outgoing AC power. Powercons fit into round holes-you can just purchase the proper-sized hole saw, lubricate with oil or kerosene (if on aluminum) and drill using a drill press. Available from Mouser or Markertek.

[lowbujit]

Ah, thanks again Brad. What sort of tool did you use for the Power cord receptacle?

An alternative suggestion:

1. Instead of IEC power cord receptacle, use a Neutrik "Powercon" chassis receptacle and matching cord plug. There are two types , one for incoming AC power (the one you want), and another for outgoing AC power. Powercons fit into round holes-you can just purchase the proper-sized hole saw, lubricate with oil or kerosene (if on aluminum) and drill using a drill press. Available from Mouser or Markertek.

Good idea. Homemade square holes suck.

[lowbujit]

Well, I just finished my tube mic. I used the pre-made PCBs, but it doesn't pass any audio. I'm getting 38V on the filament supply and 107V on the B+. Please help!

Make sure you have all your diodes pointing in the right direction. Also check your electrolytics to make sure you have the polarity correct. If this PS isnt connected to the mic when you check your voltages you will get incorrect readings. Does the tube light up?

[PeterSawatzky]

The tube isn't lighting up or getting warm. Those readings were with the mic connected, of course. I suspect the filament just isn't connected somewhere in the mic.

[seavote]

first check the dc voltage your getting coming out of the psu without the mic connected. if its still way high you can focus your troubleshooting on the psu. it should only be in the 6.3V vicinity.

[magic_mark]

I didn't read through the whole thread, but I just scanned the original instructions that came with my mics when David Royer was doing the package deal about 5 years ago. I did 3 or 4 at the time. Anyways I was scanning the instructions for someone and thought I would pass it on. PM me if you want them, the pdf is about 2 megs.

[b3groover]

They (resistors) are 1/4 watt unless otherwise stated.

Unfortunately, some of those mouser #s in the BOM are not 1/4 watt - the 750ohm is 1/8w, where as others are 1/2 watt. After I finish sourcing everthing, I'll be happy to post my BOM w/ where to get it all (just slight updates from your list, b3groover).

More so, I'm confused - the Royer article lists the resistors as 1/2 watt - why go with 1/4 watt?

'cos I'm a dipshit.

Did you update the original BOM? I'm actually going to be ordering parts for this soon. I'm going to attempt to mod two 603s pencil condensors as well as two 2001s.