help needed with arcam 290 delta integrated amp

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Hye ,
I have this pig of an amp that just wont give me any output. I have readings all across the board . Then the 2 caps c201/c202 in front of blue/green/blue feeds from toroid coil have nothing ! nothing on the line drivers on the heatsink either. Anyone come across this problem before. This thing has a plug in chip which I believe is the remote control chip and plug ins have allways been dubious in my opinion.
Just as a foot note why would a multi meter short on an amps test on a live transformer? tested this bfor no prob did it on an old sony amp (circa 80's) and got a short at two points on/off switch and black/red laminate coil? any opinions ???
thanks folks nice finding a constructive site !!!;)

I recently delved inside an Arcam Alpha 6 amp (my father's) - I obtained the service manual from Arcam after emailing their support department. If you haven't already got one, get the manual for the Delta 290.

I have a photo of the innards of your amp in front of me now. The blue/green wires coming from the transformer are the secondary output, and I believe that the caps you mention are the reservoir capacitors in the power supply. If this is dead, then you probably have a blown fuse. This is not uncommon, in fact the Alpha 6 manual mentions uprating the fuse in subsequent design revisions to avoid nuisance blowing. Check the fuse, and replace it if necessary. Be very careful to get this right - if you insert a replacement fuse into the wrong socket, you will configure the amp for 110V operation, and it will be damaged.

The "plug in" IC you mention is a PIC16C54 for the remote - nothing dubious there. I just ordered some of these from Arcam to make my own remote control receivers that will work with my Arcam handsets.

You must never try to measure resistance on you multimeter in a live circuit, you could damage it or the circuit (or both). If you are measuring the resistance at the mains socket with the amp on and power disconnected, you should see something below around 1k.

Hope this helps, the Delta 290 is a good amplifier when it works!
HI ,
Sorry did'nt get it quite right in my footnote , I ws trying to measure current (amPs ) reading , My under standing was that with meterprobes set in red>amps socket /black in normal meter ground then applied to , this was a red/black/ red? from secondary side of (lam.) coil that should give me an amps reading or current flow . would this be right?
as to the arcam , when I got it the fuse you mention was missing .The amp would'nt power up even untill this was replaced.
This I duly did ... amp powered up but no out put. Ihave checked input signal..ok. etc. I have readings all the way to like I said diodes d101/104. These are situated behind the b/g/b secondary toroid outputs . then my circuts dead in the water. so either the resovoir caps have gone down ..douptful or line drivers are blown and if thats the case then capicitors c22/23 and c123/122 may be gone as well??? any more help would be appreciated.

I can't quite follow what you say regarding measuring current. If you just connected the meter in series with the transformer primary using the high current range (and its associated probe socket), then that is fine.

From what you've said, it sounds like there has been a power supply fault. Arcam specifies what are called "fusible resistors" in its power supplies. These have the appearance of ordinary metal film types, but act as slow blow fuses under overload conditions. I belive the spec was for rupture in under 30 seconds for a 16x rated current overload. If the amp has been abused in any way one of these may have blown, and this may not be visible. You MUST get that service manual so you can check the various voltage measurements at the test points dotted around the power supply and adjacent driver stage.

Hope this helps, like I say you have a good amplifier there.
hye trwh,
I figure I've got that arcam sorted. although as I said Ihad readings across d101/104 (bridge rectifier ) seems on very close inspection that there is heat damge at the annode end of both d101,d102 .Also excessive heat from ic 202 ( LM337) situated directly in front of bridge rec. as this is a voltage regulator then I suspect that this and the diodes have gone down. can only replace and then move on to next problem that appears. although I do have a suspicion that it has been used under virtully heavy constant use and this kind of continuse use to much load for to long a time ???don't know . anyway I feel this is the problem.

That other thing on the amperage test ? well its got me as well as a mate of mine beat but I still can't figure why it should short . Tested a pioneer secondary this morning no problem ( for volts and amps) so well?????!!!!

Anyway feel free to return on above ,,,allways healthy to have a second opinion I believe . nice hooking up with you and thanks for the help
bye bye s for now ,
My 290 Integrated is sick, too.

Hi All,

just a few days ago I was wanting to listen to some music and got a bit if a shock!! I am using a 290 Integrated as a pre with a couple of 290P(power amps) in bridged mono. When I turned up the volume in the integrated to the normal 9 o'clock position, the amp relays kept on cutting out (LED to orange and no audio output) and resetting themselves. The right-hand monoblock was also resetting itself in a similar manner. When I switched from direct mode on the pre to indirect (i.e tone controls and balance now active), the amps would reset. If I moved the volume, the amps would reset. Funnily enough, I had output when I was runnng the pre in mono.

Having had a dustly input selector causing previous problems that I cured with switch cleaner, I took the amp to my bench and had a look at the insides. I was expecting to find evidence of a blown component (scorch marks etc) or two, but, except for a lot of dust that I cleaned up, everythin looked fine. I used the switch cleaner and reassembled.

When I powered up the system, the symptoms were still the same, but I noticed that the volume on the pre had to be turned way up to hear any output at all on the left channel, the right was dead and any switching made the relays click out.

Before I send the amp back to ARCAM for repair, has anyone got any clues as to what may have happened here? My thoughts are that perhaps an IC had partially failed (on the right side circuit) and then fully blown (because the gain is so tiny now that I suspect it is purely the line level of the CDP output and the 290 integrated has become a passive preamp!!!!

Any thoughts would be very gratfully received.


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