Need Help Sourcing an Audio Relay

[bob p]

I'm trying to source a replacement for a relay that's tied to the output in an audio amp. The amp (a Carver M-500t) uses a transistor logic protection circuit to control the status of a relay. The relay is a 24VDC DPST-NO type, where the relay has to be energized to connect the power transistors to the speaker terminals. Its markings are:

Taiko (or Tairo)
180008
Audio
DC24V

I don't know if its even possible to source an OEM replacement. This relay is PCB mounted, and its footprint doesn't seem to resemble anything that is available today. I had been thinking about mounting a general purpose relay elsewhere in the chassis and running jumper wires to the PCB.

Is there anything special about "audio" relays vs. "general purpose" relays that I should be concerned about? Does anyone know if the OEM part is still available?

Thanks.

[Enzo]

I could find lots of equivalent parts, but none with that odd footprint.

I still like the idea of glueing a relay upside down in the same spot and running wires down to the board. A swab of contact cement and it won't be going anywhere.

It is a speaker relay, not a small signal type. A power relay if you prefer. The contacts don't handle a lot of voltage - whatever the high rails are - but the current can be several amps.

Beyond that most any 24v relay should work as long as its coil doesn't over tax Q207.

I don't know who the Taiko people are, but try to find them. Googling the part number got me nowhere. I sincerely doubt it was a custom part.

[bob p]

I found the Taiko people.

http://www.taiko-device.de/

They make automotive relays, and it looks like they don't make anything for audio any more. I emailed their North American contact person yesterday, giving them the part number, and asking for help. I'm not holding my breath.

I have looked at general purpose power relays. In fact, this one by Omron arrived from Allied today with my order of ICs and caps that we had discussed previously. Due to a mistake on my part in the manufacturer's part number, I ended up getting the flange-mount version of the relay instead of the version that snaps into a mounting bracket. The idea was to put the mounting bracket in a free space on one of the chassis walls, mount the relay horizontally, and run jumpers to the center of the PCB where the original relay was located. Unfortunately, the flange mount has the mounting points spaced too far apart to fit anywhere in the chassis, so the relay will have to be sent back. The version that snaps into the mounting bracket (this one) is what I thought I was ordering. Its physically larger than the OEM relay, but its a tad smaller than the relay that I have, and it will fit into the mounting clip. It looks like it will be fine for the job. Now its just a question of whether its electrically suitable.

These two Omron relays are the same unit in different cases. I need the smaller one that fits on the mounting clip because of size constraints. They use 80mA at 24 VDC. I'm hoping that's not too much current for Q207. The relay contacts are rated for 25A. I'm thinking that should be plenty. They have a silver alloy on their contacts, in contrast to what looks like gold contacts on the OEM "audio" relay.

[bob p]

Now this is interesting. On the last page of the spec sheet, I found this comment that I hadn't seen before:

"G7L Relays with test buttons must be mounted facing down."

Yes, my relays have test buttons. But I have no idea which direction they consider to be "down." I was thinking that the e-bracket that they sell is supposed to mount horizontally on the bottom of a case, or that the flange mount brackets are supposed to be mounted on a horizontal surface. That orientation puts the spade terminals facing up. In that orientation, the writing on the side of the relay is upside-down. I guess that's what they mean by facing down. Damn. I was planning on mounting the relay sideways. Now I'll need to fabricate an L-bracket or something.

[Enzo]

2SC1509, right? 80v 500ma

80ma ought not be a problem for it

[bob p]

ah, yes. thanks for looking that up for me.

any idea why that relay would be position sensitive?

[Enzo]

No, unless the contacts were mercury wetted or something. I'd have a hard timer thinking the armature is so delicately balanced that gravity would affect it pulling in if upside down. I have no idea. COntact the manufacturer and ask. or see if the data sheet has application references.

Perhaps google "relay orientation." Although you'd likely get information on joining a track meet.