• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Eico HF-22's total reassembly.

Al,
Thanks for the nod...I'm happy.

sKiZo,
I really had considered all my options...at least all I could think of, including press or rub-on letters. When I was younger, I worked in a sign shop and did hours and hours of Letraset lettering. There, I had an apparatus that kept the Letraset sheet on a constant line. The idea of doing it freehand was more than I wanted to tackle. Especially the chassis panel that contains all the info.
Actually spending the time doing the touch ups was not so bad. I just put in an audio book and got after it. Figuring the best approach took some time.

Placed my Mouser order last night. I was able to get about 98% of what I needed there.

GordonW,
I decided to go with your recommendations;
C1a & b - (1)47uf / 450v
C2a - 100uf / 450v
C2b - 47uf / 450v
C4 - 100uf / 100v
R12 - 5.1K / 1 watt

Everything else, I went with equal value or in some cases, higher voltage replacements.
The only items I still need to acquire are two tube shields, power cords and misc. nuts, bolts and washers.

Tube shields...I was informed that tube shields on my 800c isolated interference from the units MPX section. So why are they necessary on these amps?

Power cords...is a grounded plug recommended or just a polarized plug?

Thanks

martin
 
I'm pretty sure you should use a grounded plug. If the rest of the grounding scheme is correctly done you won't have any ground loop problem.

I'll be interested to hear if there are any other views, as amp grounding is an important area for sonics and safety.
 
Martin -- I have found that the best compromise for safe and quiet operation is to use a polarized plug with a safety cap from the neutral side to the chassis. Green wire grounds are a direct invitation to ground loops -- especially if other equipment in the system is earthed independently such as cable or satellite systems are, or has their own green wire ground. Everyone will have their own opinion regarding grounding and safety, but over the years, I have found this method works very well, and minimizes the ground loop problem.

Dave
 
marloubow said:
Okay...
Here's the finished chasssis'. Their not perfect, but I can live with it.
Below is my approach. In hind site, there a few things I would do differently. But like any restoration, there is a "point of no going back".
Good enough:thmbsp:

martin
Click to expand...

Wow. That looks pretty nice. I was scratching my head when you originally said something about the "camo" look. However, these are basically a total refinish with the exception of cleverly preserving the original lettering. Nice job! :thmbsp:
 
dcgillespie said:
Martin -- I have found that the best compromise for safe and quiet operation is to use a polarized plug with a safety cap from the neutral side to the chassis. Green wire grounds are a direct invitation to ground loops -- especially if other equipment in the system is earthed independently such as cable or satellite systems are, or has their own green wire ground. Everyone will have their own opinion regarding grounding and safety, but over the years, I have found this method works very well, and minimizes the ground loop problem.

Dave
Click to expand...

I agree 1000% with this. I've had the exact same experience here.

What use is it to use a green ground wire (third wire), if you just have to then use a ground-breaker on the plug, to get rid of a ground loop? Especially on a device that can safely use 2-wire power cables?

Regards,
Gordon.
 
I must confess that I've had the same problems when using other independently earthed equipment, such as a preamp.

Gordon, what conditions would you specify for 'a device that can safely use a 2-wire cable'?
 
Polarized it is then.
I don't suppose it needs to anything exotic, does it? Will a generic $3.00, 9 ft'er from lowes or home depot do the job?

Any specific value for the ceramic cap?

ohighway...thanks for the nod! An old friend of mine had an aluminum bass boat that had been painted many times. When he went to sanding it, it looked a lot like my chassis' before paint. My friend left it sanded and unpainted and called it "camo".

A note about the Vaseline trick. If you use a thick paint, such as the hammered metal or apply several coats of regular...beware, a ridge will be present at the edge of the Vaseline. Which can be knocked down with a little lacquer thinner...sheeesh....more work. :thumbsdn:

A new question...
Seeing how these units arrived totally stripped down, how can I test the transformers to make sure they are operational?

Thanks

martin
 
Dandy said:
I must confess that I've had the same problems when using other independently earthed equipment, such as a preamp.

Gordon, what conditions would you specify for 'a device that can safely use a 2-wire cable'?
Click to expand...

In this case, it's a device that is normally not even touched when used- that's one aspect. A preamp might be a different affair, to some.

Also, the transformers and such were made to be used with 2-wire cabling (that's how they were made). If the unit was built, as a stand=alone piece, from a reputable company, with a 2-wire plug, then it's presumably safe that way...

Regards,
Gordon.
 
Thanks Gordon, I was interested in what your thoughts would be on a preamp.

(I did a bit of hum tracing with a professionally-built valve phono stage and valve preamp and a self-rebuilt Dynaco ST70 and tried successively disconnecting the 3rd ground wire. It's the bespoke built preamp that introduces the hum, so it's been replaced by a pot for now!)

I guess your reply suggests that Martin should follow the original amps' layout closely.
 
Well,
Just about ready to really get after these Eico's. The assembly instruction are pretty straightforward. Hopefully the hardest part is behind me.

One thing about this being a kit with assembly instructions. It makes it somewhat easy to build, but lacks on "teaching" about electronics or even briefly identify the components. "Connect C17" or "R6" to "tab A" is about the best you get.

Gee...I'm feeling so cheated. :D

Been busy tying up some other projects. Don't want my attention divided. :nono:

I've got just about all I need. All the components are checked in.
Still need a pair of tube shields. I'm sure they'll show up sooner or later.
The tubes are a real mixed bag. Just have to cross that bridge when I get to it.

Everything got a new coat of paint. Decided to go two tone on the power transformer. I like the way it looks.


The cans are for show only...at least at present. Going with Gordon's recommendations. Plenty of room below. Plus, I may need the $'s I'd have spent on new can's, for tubes.
I sanded, buffed and polished them to make them presentable. Just have to be careful not to grab them when changing the chassis' position.

The stand has been invaluable. After all the work on the "looks", I'd hate to scratch it up. As heavy as these units are, I know that eventually I'd bung something up without it.


Will keep updating as I start wiring or have questions.

Thanks

Martin

DSCF0082.jpg


DSCF0080.jpg


DSCF0085.jpg


DSCF0077.jpg


DSCF0072.jpg


DSCF0070.jpg
 
WOW- Just - Wow -


The paint job, the stand - What a wonderful, detailed job you are doing -
Hard to believe how those started out vs. the way the look now.

Quite a standard to try and emulate!

CC
 
Hey guys,

I have a CL-90 inrush limiter for each unit...where do you guys suggest I install them?

I cleaned up a copy of the final wiring diagram from the assembly instructions. I had to remove all the assembly indicator arrows and component designations because the sams numbers and the Eico assembly numbers are different.

IE; C8/Eico - C10/sams. Could get confusing, but that's on my shoulders.

I'll ask questions using the sams numbers.

Thanks
Martin

Fig5scancopy-1.jpg
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom