Problems with my Nikko TRM-800

[xasm]

Hi all,

I'm curious to know if anybody else has the same problem as I do with my Nikko TRM-800 Stereo Receiver (~20 yrs old, maybe more). Basically what happens is that if the volume knob isn't loud enough then no signal will come through either of the 2 speakers. However, sometimes you can hear only 'windows' of the source when there is a part in the song that is loud enough (such as a heavy bass, or some loud kick drum hits).

So it kind of acts as a gate to which I can't set the threshold. Lots of distortion when this happens too.

Just to note, this happens on the phones jack on the front as well, so I know it's not the speakers that I'm using. I've also tried different inputs on the unit, and using different sources, to no success.

Anyways, I'm looking for the Service Manual for this unit and wondering if anybody here has a copy of it. I've already emailed one on-line companies (www.antechlabs.com). Has anybody had any success with this company?

Thanks,
Tim

 

[r0cket-]

First guess is that the volume pot is dirty. You might try some contact cleaner on it, or just replace it completely.

 

[xasm]

Ah yes, forgot about that stuff. I had some a while ago but I seem to have misplaced it 🙁.

Thanks,
Tim

 

[Dave Kilpatrick]

I have a nikko trm 800
I would like to know how much power it has ?
and also I have the same problem with my volume control but not that severe!
Dave

 

[anatech]

Hi Tim,
Before touching the volume control, give the speaker protection relay a tap. See if this makes the sound cut in and out.

-Chris

 

[PMik]

2x 60W/8Ohm ...and was introduced in 1975 😉

 

[danteOK]

same problem with volume & channel reduction

last time I had mine opened (real good amp, btw! - 3 separate speaker sets!), the volume control showed to be encapsulated and impossible to spray contract spray into. How, what, please?

Does anyone know of a souce of replacement parts?

Also, one channel falls in and out - someone told me that it's probably a relay "hanging" - but how to "unhang" this? OR determine that this is actually so and not the amplifyer for one channel?

Does this babe go for anything today? Worth anything, I mean?

thanks.

 

[mrshow4u]

The speaker relay becoming intermittent is pretty common, for the sets that use one. A tell-tale sign that the relay is "crusty" is to turn up the volume (a bit) and see if the audio punches through. If this is a receiver, I assume the tape monitor switch is already set to source? Sometimes the headphone jack is wired before the protection relay. If this is the case, the headphones might work, while the speakers don't. The good news: a 20 year old amp with a relay, should have a fixable relay. If you determine the relay is intermittent, I'd recommend removing it, taking off it's plastic cover, remove it's armature spring, and burnish (carefully) it's relay contacts. Reassemble and resolder and you're back in business. I hope it's the realay. It's a common failure. If it turns out to be the relay, you can improve the reliability by having the volume down at turn off and turn on. The pits that end up on the relay contacts are due, in large part, to the contact "bouncing" when closing while delivering current to an inductive load.