I ran into a problem last night with my Partner ACS system. For those who don't know, I have an R8 (509) processor in a 5 slot carrier with 4 308EC expansion cards. While making some test calls (setting up a new Voip provider) I discovered that extensions 10-18 had a tone overlaid onto the talk path that sounded similar to a 1kc tone. May have been a bit higher pitched, but that isn't the point. When I tried my buttset across the second pair to each extension, instead of the usual low pitched buzzing that's always there I also heard this tone. It was very loud on this second, data pair. Now, I've already fixed the problem, but I wanted to post it in the off chance someone else runs into this problem. I know these systems are getting rarer, but there's still plenty of them out there, and it wasn't a very difficult fix if you have any level of electronics knowledge. The problem was the power supply board in the processor module, and more specifically, dried out electrolytic capacitors on said board. The easy fix, besides just replacing the processor, is to just replace the power supply board with a new or working replacement. The other fix, which still isn't all that difficult, is to replace the faulty capacitors with new ones. I chose the second route for two reasons, one- I have the skill and the tools to do it, and two- because I'm cheap and impatient. There are a total of 10 electrolytics on the PS board and it's all thru-hole, so it's a pretty easy job. I also didn't want to wait for a used, questionable replacement to arrive. Anyway, it probably took all of 20 minutes to make the repair and all the extensions are dead quiet again. So, if anyone happens to run across this weird problem, this is what fixed it for me. Just wanted to add this to the general knowledge base. Thanks.

Thanks for letting us know about the tone being caused by the processor PS. Not run into that one yet.

New (not used or rebuilt) power supplies can be had from RS for probably what it would cost you for those caps and shipping.

-Hal

I went to the local electronics store and it was $12.75. When you say "RS" are you referring to Refurb Supplies? I looked and couldn't find one on their site

I abbreviated RS because I didn't want the "unwashed masses" that come here to know where we get our parts from. Doesn't matter because their site sucks, I know I have gotten them from them for the ACS R6 and I can't even find them there. I would give them a call if you want to pursue this but it looks like you have it under control. Can't beat $12.75 anyway. Most times when these power supplies fail they burn up, so it's not a matter of replacing some caps.

-Hal

I didn't realize you were trying to be hush-hush. Sorry about that.

I found their site some time ago, just from a google search trying to find LCD panels or something for a euro II phone.

I wouldn't mind having a spare PS on hand in the off chance this one grenades itself. I've repaired plenty of switch-mode power supplies and I've seen lots of different failure modes.

I think I was fortunate to catch it when I did, preventing it from deteriorating any further.

I used to have drawers of caps but I didn't have most of the values in this particular PS. I used to buy old Merlin 206's and 410's on ebay for not much more than the cost of shipping, usually DOA. I'd recap the PS board and occasionally replace a polyfuse to bring dead ports back to life and then sell them. I could turn around two or three 410's a day and make some good money. People like to hang on to those old things for some reason.

[Don't worry, Paul, I still have the one you gave me. ]

They used to be the standard in restaurants and food service. Now you find anything.

-Hal

I was wondering. Take good care of it.

Actually now that I think about it, RS has a dealer log-in which I think had a better selection. Now it just shows dealer prices.

-Hal