DrV

That's great - thanks all. I went for the second eBay ones in the end as the picture showed a red spot which matches what I've got. Thanks to KevinE for pointing that out and to kgallen for spotting the eBay ones. And probably more nutritious 😉

Thanks for all the suggestions (and the PM). I've enquired whether there's a good one available to measure but I now have some things to research. Thanks all.

It's certainly not a standard festoon of the type we used to get in car courtesy lights etc. It's wire ended. Will take a photo tomorrow.

I have been asked to repair a couple of Apart Mask 8 speakers. They have the usual wired-in incandescent festoon lamps to protect the tweeters and these have blown. I contacted BiAmp who now own Apart and they responded They were, however, prepared to sell the complete crossover assembly. Does anyone else think that incorporating an incandescent lamp into a product and then not being able to supply a replacement when it blows is somewhat short-sighted from an environmental point of view. Also, does anyone know where I could source two? For guidance, the cab is rated at 300W and, according to the spec, the LF is rated at 200W. Dave

I already explained this in my post. In summary, if you've got a supply to the pump which only ever goes -ve w.r.t. neutral, and the pump diode only conducts when the supply is +ve w.r.t. neutral then there will never be any current flowing in either direction.

The diode is there effectively to change the bipolar sine wave of the mains (with a current pulse every 10mS) to a series of single sided pulses, one every 20mS, with a 10 mS dead time between them. I believe this is because the pump armature wouldn't be able to respond at 100Hz but is ok at 50Hz. The same effect could be achieved by using a permanent magnet armature but this would be more expensive than a diode. Now, if the pump is being driven by a thyristor, rather than a triac, that too will produce pulses of a single polarity. If these happen to be, say, negative pulses and the pump diode is oriented to use positive pulses the diode in the pump will be reverse biassed and block the current. Reversing the pump connections turns the diode round and all is well. Edit: if your mains frequency is 60Hz rather than 50Hz then read 8.3mS and 16.7mS respectively for 10mS and 20mS above

If you need the original processor repaired then let me know.

The description for code 6023 is Analogue Rectifier Failed. I think this refers to the Analogue Precision Rectifier which takes all of the multiplexed analogue inputs into the processor chip. This is IC 40 etc. and this suggests it has failed its self test. Looking at the schematic it could be the chip or its associated passives, or the dummy load that the processor puts on it during self test. I can probably repair it for you and I have some spare processors here. Why did you swap it in the first place? By the way, if Kazeja chimes in that I've got it all wrong then listen to him, not me, as I've never actually seen that fault! Just working it out from the fuzzy schematic.

It could be that they haven't paid their bills and are having trouble getting the manufacturer to deliver. Either way the "optics", as they say these days, aren't good.

That's exactly right. You only need 100V to get the full nominal output. Any amp which is capable of driving 20 or 30 volts will give you enough level to identify speakers. In fact using the minimum required to be just audible will probably help overcome the problem of distinguishing multiple speakers in earshot that Brian mentioned.

With high volume manufacturers like Behringer, pots are often slightly custom versions of standard parts from the likes of ALPS. If you buy half a million pots you can have any combination of value, spindle length, spindle style, orientation etc. you want. Can you post a picture of it? It might be a standard one.

That gave me a laugh😉

From my years of bodging motorbikes when I was a teen... I see you've already got the Plusgas out and copious amounts of that and a lot of patience will help but another aid might be to tap it all the way around with a hammer and drift or chisel held tangentially to the ring. Tap it in the unscrewing direction of course. You have a good surface to tap against with all the knurly bits.

Silly me - yes, could easily be inductors. More likely in fact.

220 in that size of case almost certainly means 22nF but if that's the only marking then you'd also need to specify a suitable voltage and dielectric type. The working voltage needs to be at least the same as the supply rail voltage but ideally around twice that. So if your supply is 40-60V you'd fit a 100V part. Dielectric type would be polyester film. With a cursory search I can't see any cylindrical, radial leaded ones like that but there are plenty of axial lead or rectangular box types available. Edit: are you sure the caps have failed and that the black goop isn't just the adhesive holding them down? It does seem a different colour from the rest though.