Dead Citation 22

[Dave B.]

A friend of mine passed recently and willed to me some very nice equipment. One piece, the SS Citation 22, was always a favorite of mine when we got together to listen to the classics.

It's been several years since I received the amp, and the other day I decided I would get it out to see what it sounded like in my own system. After a careful examination, owner's manual review, and set up, I turned it on and it played for a while then just shut down. No panel lights, no smoke, no nothing.

I unplugged it, took it out of the system, and tried to find an obvious problem. I suspected a fuse (couldn't find one), but other Web information I've read seems more ominous.

When I put a meter on the power cord plug, I found that there's conductivity regardless of the on-off switch setting. This may not mean anything because I'm a relative idiot about all things electrical.

Any thoughts from the H-K crowd here? Thanks, as always.

Dave

 

[Freddymac2]

Someting failed drew high current and welded switch contacts and then blew the main fuse. The wrong size fuse may have been put in after the original fuse was replaced.causing excessive current.

 

[Dave B.]

Thanks, Freddy. That's what I feared.

Can I locate the fuse(s) easily? I've had the cover off but didn't see anything that looked like a fuse.

Dave

 

[Freddymac2]

Yes, but if you find it will most likley blow again. Highfiengine might have Service manuals but you need to know what you are doing. Your outputs or something are shorted.

 

[Dave B.]

Just checked the service manual schematics, Freddy, and saw the fuse area. But, as you caution, no way am I sticking my amateur nose in there. So, off to the repair shop we go. Thanks for the help.

Dave

 

[Blue Shadow]

Keep us posted on this. There are a few of these in the community and if we need to do some preventative work, be nice to know.

 

[Dave B.]

Will do, Blue. Might be a while, though, since I've kind of hit the Mac lottery and have just (by fate) acquired two MC2000s. That will no doubt keep me occupied for a bit, but I am definitely interested in resurrecting this Citation 22. It's one heck of an amp.

Dave

 

[fred soop]

With the main fuse open, there will still be continuity across the line cord when the power switch is on. There is a separate, small transformer that is not fused that powers a relay to connect main power via the fuse to the main power transformers. There are also 4 secondary fuses on the main PC board on the AC to each channel. Unlikely that all 4 would blow because any catastrophic problem would be limited to one channel. The Citation 22 uses a separate power transformer for each channel and they could be disconnected individually, then each channel tested with a DBT (dim bulb tester) or variac with ammeter.

 

[Dave B.]

That's great information, Fred. Thank you! When I take this unit to a tech, I'll mention your comments, without trying to tell him his business.

Do you happen to know if the Citation 22 has a thermistor (I haven't taken the time to look that up)? I'm wondering if after sitting for so long a cap might have failed shortly after powering up.

Dave

 

[nj pheonix]

One point of note.
Not saying its the case. Some amps with big power supply caps after sitting idle will blow fuse when powered on. Caps need to reform. If it ran a little before it failed that's likely not the case. If you powered on and poof, you might want to put it on a variac and bring it up slow with a new fuse. It may in fact be fine. If it blows again, bring it to the tech

Rereading the opening statement, i tend to doubt the scenario i just described

 

[Dave B.]

Thanks, nj. That's why I asked about a thermistor. Mac amps, for example, use thermistors to protect caps from an initial surge after a long sleep. There was no poof, but whatever happened, happened very shortly after powering up.

Dave

 

[fred soop]

No thermistor. Is the "Protect" light illuminated on the front panel? There is a circuit that mutes the amplifiers for a few seconds after initial power up and problems in that circuit will cause both channels to shut down. I had a leaky capacitor in that circuit in a Citation 24 (almost identical to Citation 22). Not very many things that would affect both channels.

Actually, do ANY of the front panel lights illuminate? If not, then we are back to the relay at the AC line.

This generation of HK equipment does have some issues with capacitors being run too close to rated voltage, such as 25 V caps running at 24 V. I recapped a Citation 21 preamp and eliminated an intermittent problem as a result. It was faster to recap completely than to actually troubleshoot the problem.

 

[Blue Shadow]

I recapped a Citation 21 preamp and eliminated an intermittent problem as a result. It was faster to recap completely than to actually troubleshoot the problem.

Just counted the caps in the Cit 25 preamp. More than a Pioneer SX-1050. Hope it keeps working.

When I got my 22, it would not come out of protection. One cap changed and it works just fine. Maybe I ought to consider recapping it sooner rather than later.

 

[Dave B.]

"Protect" light illuminated on the front panel?

Negative. No lights at all. The unit is completely dead.

Dave