IEC modification to ST-70 chassis

This is my first post. I've been quietly reading along and just placed my order with Bob.

I've been doing a bit of looking around to see if there are good suggestions on how to put an IEC connector in for the power cable. I looks like a short (or right angle?) connector is needed, and the short may occur by making a standoff so the connector sits a bit more proud of the chassis (and gives room to the transformer in the back)?

Has anyone done this and can either comment or point me to a thread, as my searches have run a bit dry.

Thanks!

Filippo

I thought about putting an IEC in a different build (not an ST70) and ultimately concluded it wasn't worth the added effort for me. I had the socket and the room, but didn't have an easy way to cut the opening. I literally cut the end off of the chord and wired it as Bob suggests, other than connecting the ground to one of the power transformer mounting bolts.

fmorelli wrote:This is my first post. I've been quietly reading along and just placed my order with Bob.

I've been doing a bit of looking around to see if there are good suggestions on how to put an IEC connector in for the power cable. I looks like a short (or right angle?) connector is needed, and the short may occur by making a standoff so the connector sits a bit more proud of the chassis (and gives room to the transformer in the back)?

Has anyone done this and can either comment or point me to a thread, as my searches have run a bit dry.

Thanks!

Filippo

Yes, i installed an IEC in a vta-70.

It's located to the right of ( as seen from the back) the main transformer. The biggest problem was
that since the vta is made by stainless, i had to have it milled away.
The IEC choosen was one with a built-i fuse, thus making the supplied fuse unneded.

I did send photos to bob, he might be able to dig them up and post it here...

I've done it several times.  You have to be careful with clearance to the transformer bottom bell housing.

I installed an IEC inlet on the same chassis.  The chassis is strong and took me a couple of saw blades and drill bits to get the chassis opened up then a lot of filing to size the hole.  There are several types of inlet connectors and used one where the connector opening sits proud of the plastic mount (see pix below or post above).  This saves a couple of millimeters of clearance on the rear versus connector openings that are flush with the plastic housing.  After mounting the solder pins can bend over to ensure enough room to the power tranny.  

IEC C14 Inlet Picture

Thanks guys. I'm wondering if anyone has specific IEC part references - for example, with right angle connectors or particularly shallow plug body?

The stainless is a bit of a headache, but I have a shop at the house so I'll work that out. Glad to post pictures and such when I get that far!

Filippo

fmorelli wrote:Thanks guys. I'm wondering if anyone has specific IEC part references - for example, with right angle connectors or particularly shallow plug body?

The stainless is a bit of a headache, but I have a shop at the house so I'll work that out. Glad to post pictures and such when I get that far!

Filippo

Here is the one I used and in the photo above.

http://www.mcmelectronics.com/product/28-12532

PS, keep in mind I installed this in an original non-stainless chassis that is MUCH easier to file away than the newer stainless ones.

What would be great is to find a male receptacle with right angle soldering connections in the back. My other thought is to machine a "washer" for the IEC so that it sits more proud on the chassis face. Seems like a simple way to solve, maybe?

Filippo

kaner wrote: other than connecting the ground to one of the power transformer mounting bolts.

Hmmmmm ... no hummmmmm?

Back in the '80s, when hi-fi manufacturers were starting to offer IEC receptacles on their gear for people who wanted
to use high end a/c cords, at least one company, Audio Research, listened to its gear with power cords hard wired in, and
with IEC receplacles. They found that the EIC junction degraded the power connection versus hard wiring. I guess that since then,
they have come around to the view that if people insist on wasting, er- spending money on exotic a/c cords who are they to question
it?

Interesting ...

Filippo

As shown in the pictures i sent to bob , mounting an IEC besides the main transformer is possible, thus a very long IEC well might be used.
It will occupy the space used by the mains fuse, but since IEC wells with fuses are available that is
no problem.

( Triode has IEC as standard on their ST-70 ... )

I'm certainly not criticizing the lack of an IEC, just was interested in possibly changing over to it. As for originality, that seems an arbitrary argument. I like the newer banana plugs and they certainly are not original, and in the same location as the power cord so ....

Filippo

sKiZo wrote:

kaner wrote: other than connecting the ground to one of the power transformer mounting bolts.

Hmmmmm ... no hummmmmm?

No hum whatsoever.  If your worried isolate your ground.

I have moved the photos of my VTA-70 with IEC connector.
The IEC is a model that has a built-in fuses, thus i can skip the supplied fuse, in it's place is an isolated connector for controlling the added SSR ( the SSR is also visible on the photos)

http://n.manet.nu/ST70-IEC.jpg and http://n.manet.nu/ST70-IEC2.jpg

The worst was that i had to use a mill to create the IEC hole as stainless is difficult to cut.