Grommes 28PG recap

[specialidiot]

I picked this up from a local AK guy, your basic EL84 PP amp. All the AX7's are Telefunken, as are the rectifier tubes. EL84's are labeled Grommes, Made in USA but unfortunately one of them disevacuated on me so I stuck in a similar looking RCA.

Sounds pretty good, but not quite there. A little research shows that 50 year old Tiny Chief caps should be replaced, so I spent last night doing that.

I found some replaced resistors, one of the 'lytics below replaced, and I think the bigger mulit-section FP is new. Anyone know how to read the date codes?

Also, I thought these were all factory built but they must have had a new guy on the soldering iron, there's way too much solder on nearly every joint.

All the Tiny Chief's are replaced with 716P's, and I cleaned up the pots and switches. It sounds a lot better.

Schematic here.

 

[doucanoe]

I picked this up from a local AK guy, your basic EL84 PP amp. All the AX7's are Telefunken, as are the rectifier tubes. EL84's are labeled Grommes, Made in USA but unfortunately one of them disevacuated on me so I stuck in a similar looking RCA.

Sounds pretty good, but not quite there. A little research shows that 50 year old Tiny Chief caps should be replaced, so I spent last night doing that.

I found some replaced resistors, one of the 'lytics below replaced, and I think the bigger mulit-section FP is new. Anyone know how to read the date codes?

Also, I thought these were all factory built but they must have had a new guy on the soldering iron, there's way too much solder on nearly every joint.

All the Tiny Chief's are replaced with 716P's, and I cleaned up the pots and switches. It sounds a lot better.

Looks great Jeff! Those Grommes integrated's are pretty nice. What do the Tiny Chief caps look like? Not sure if I have seen those before.

RC

 

[specialidiot]

Looks great Jeff! Those Grommes integrated's are pretty nice. What do the Tiny Chief caps look like? Not sure if I have seen those before.

RC

Thanks Ron... I don't have my Eico HF-81 handy - I'd love to A/B those circuits. This guy seems unique in that all of the small signal tubes are 12AX7's. I'm not sure what that means but I'd imagine you could design around that. Anyone have any input on that?

Here's a pic of the Tiny Chiefs I used to list them. I've found that some have actually sold, so I may was well get something out of them, right?

 

[specialidiot]

Solved the Date Code mystery here, thanks to search and Tom Bavis.

235 is the code for Mallory, 8722 is 1987, week 22

My date code is 235933x, so I figure 1993, week 3? I'm good with that. There are a couple other 'lytics I'll probably switch out.

It's sounding mighty nice with my Big Bobs right now, btw.

 

[doucanoe]

Nope, I've never seen those before.

Sounds like people must still like them though if they are will to pay for used ones.

RC

 

[ejfud]

What's this look like from the front?

Nice work as always Jeff.

 

[KGBMAN]

Nice unit!! I've been hunting for one of those for some time.

 

[specialidiot]

What's this look like from the front?

Nice work as always Jeff.

Thanks Gary.... while listening yesterday one side started dropping out. I hoped it was a socket or something, but ended up being a 6bq5 tube. Thankfully I had a spare.

This is the seller's picture I highjacked, yes I have the cabinet and the tuner, and a Garrard 210 changer.

Nice unit!! I've been hunting for one of those for some time.

Maybe your search has come to an end...

 

[gearhound]

Looking REAL nice!!!

Steve