KevinE

as long as their invoice has a GB VAT number on it you claim the VAT back just as you normally would. It's no different to how Mouser, a US company, have been doing things for years

 

I've just had an invoice from Thomann and can confirm what others have said, you treat the invoice as though it were from a UK company regarding the VAT, as the previous 'intra-community' rules no longer apply here. Their GB vat number is registered to a UK office (a cross-border VAT agent in Brighton) and as far as HMRC is concerned, that is where the sale has taken place. Where the goods are warehoused is largely irrelevant.

 

I bought some 2500W xenon lamps as I couldn't get them from a UK supplier..ironically.

make sure the 3-wire ribbon to the fan speed control opto is making good connection as I think on some board revisions it gets its op amp 0V reference through it. I do know it can cause baffling symptoms. Also the power LED is involved in generating one of the references, in certain revisions (not all boards are the same!) so make sure that's lit ok.

In very dirty amps I've had tracking underneath the jumper cable that joins the two boards...under the pcb header itself.

I've had the odd minimelf 4148 go leaky, the odd metal oxide resistor go high and that sort of thing.

What was the Q205 mod, the one where it snaps off at board level? Later ones held the pcb tight in a rebate machined into the heatsink.

 

Sometimes the ribbon that connects the rear DIP switches to the ch1 ® pcb can go open in random places at the transition plug at the back. It can cause weird symptoms.

I've had a faulty transconductance amp which causes mischief for example allowing it to drive one way but not the other.

 

PS if the plating-through fails on the main bus caps (due to stress) it can interrupt one of the power DC lines mid-circuit with interesting results. However I'd have said this was a problem with mobile setups rather than an install.

worth mentioning that by April 2022 all VAT registered traders regardless of turnover must move to digital tax records by law.

I would suspect the motor losing torque, proved by bobbing a known good motor in there.

did anyone get anywhere with contact info for Turbo products? The main kidderminster number returns a 'number not in use tone'.

Mine arrived yesterday evening.

I gave up in the end, and rang the freephone number. Unfortunately, it only keeps you on hold for 14 minutes then kicks you off. 4 tries and an hour later and I managed to get an online chat window, she gave me a different number. When I rang I got music on hold for One Hour and Twelve minutes. Then a woman answered saying she was working from home, she explained that the web application was coming up with errors because I didn't have a credit history and they used a credit agency to double-check your identity. She asked me the date when I submitted my last tax return which luckily I knew as it was christmas eve, and she then entered the application manually through the keyboard.

 

Just as I was putting the phone down a courier called in and said 'good afternoon!' which was met with incredulity as I'd started the application at 8am.

 

 

 

not going smoothly here, website reports it can't verify my identity, which is strange because it never has any problems when I log in to pay them money

I've just measured an XS 'straight' tube and its 2.3mm OD. Very thin wall. The manual recommends deep cleaning with dilute hydrogen peroxide. I dont have a curly one to check.

certainly more clever than the unique, maybe why they have a slight reputation for being temperamental.

For example the heater triac going short will not lead to overheating, just a flash code. I saw a unique overheat such that the glass wool insulation became incandescent. This was due to a bodged repair where the thermocouple had been connected backwards.

 

The fluid pump is also short protected so it can't continuously pump under fault conditions. The punp has an undersized supply fuse, and the triac keeps the current lower than the rupture current. If the triac goes short, the fuse blows and it fails safe.

 

The tube heating current is 30A.

here's an excerpt from the manual describing 'autocleanse'. Certainly the XS versions go through this at shut down as well.

 

Circuit Action -

At switch on, initial readings will be taken and the circuit allowed to settle.

A cleaning phase will always be entered. This involves the air pump, the fan, and

current control to the tube. The tube will be taken to a much higher temperature than the

normal running temperature.

The air fan will pulse, and a reduced current flow will be issued to the tubing. At

around 300C the main fan will stop, whilst current flow will continue. At a higher

temperature level, current flow will cease, and the tube allowed to cool. Again at

around 300C the fan will start pulsing, to cool the tube. The current will be re-applied at a lower temperature, and the process repeated several times until, finally, the fan will be

lower temperature, and the process repeated several times until, finally, the fan will be

switched to full flow, the temperature switch points changed to normal operation and the

main routine entered.

This is a simple heat up -cool down -fluid pump -heat up -cool down etc.

Software fail sensing is continuous and is present in both cleaning and operational

modes.

yes, directly heated. The later ones use a straight tube around 4 or 5 inches long and a small rodding drill is stowed inside the cover for convenience.

These have a strict controlled shut down like the Unique if blockages or spitting is to be avoided. There's also controlled start-up which is supposed to gently heat and eject any stray fluid before entering normal running mode. I suppose it's designed to prevent burning and coagulation.

 

Of course this is all academic when the thing is installed under some stage and turned on and off by switching the mains socket in the DJ box.

looks like an earlier version of the later 'XS' units, they also used a fishtank pump, and I agree they shouldn't be floating about, but the screws look like they were wrenched out at some point.

I know the later ones used a different heater triac and toroidal transformer, a little fluid bottle and a simple straight heater that can be rodded with a supplied tool through a little hole in the cover.

Otherwise I cant see anything to worry about.

The heater connections must be scrupulously clean and well made otherwise it will throw a tantrum.

These were an expensive machine to just throw away. Do you want to take a few pics of parts that make you suspicious, and then put them on here instead?

I supplied some VX12's last summer as replacements for some DMT12's (they had been used in a disco and the drivers destroyed)..and these were not bi-amp-able. Made in Scotland apparently, and very nicely finished. Two of them were damaged by the courier; one was replaced under warranty (cabinet dented) and the other repaired, handled by Kidderminster within 2 days.

isn't this sort of thing likely to lead to potential stability issues? After all, there's no error correction. Does it have to be your actual DMX?

as far as I know, the technohaze sensor uses the heatsinking properties of the fluid to keep it cool; the control pcb heats it, and if the temperature rises so far, it assumes it's become uncovered. It's soldered to the end of a piece of wire then covered in a heatshrink boot. Might just have fluid in it and need drying out and re-sealing.

The Formula Sound AVC2 is designed to prevent people blowing-up speakers. It works. It is used by sound system contract rental companies to protect their installed assets when speakers and amps are used by people who are likely to blow them, either by accident or on purpose. It must be set-up before use.

 

Take a look or chat to them.

 

Formula Sound AVC2

there must be some sort of control from the led driver otherwise how would it turn the LED off if it overheated? For example many of the better fixtures will switch the led off if it detects one of the fans has locked. LEDs are generally current-controlled, so once you're certain the psu should be giving full output, take the led load off and measure again. If you're certain its 24-30V then a small 24v lamp across it will give a better indication than a digital meter if we're looking at a pwm signal.

 

A power led will normally light to some extent with a few milliamps across it, try powering it seperately from a 9V battery or two.

I have a mobile DJ client who is mad on graphics lasers, and a few weeks back he brought me a 'little' RGB 3W disco laser for repair. I had to really shout at him to stop staring into the laser window at a distance of about 6 inches while he showed me the fault. (luckily it was dead). The philosophy seems to me, they're cheap and easy to obtain, so they can't be that dangerous.

Some shoebox sized ebay disco lasers are quite able to burn skin at 3 feet.

Osram do special leading-edge thyristor dimmable GLS led lamps, I've got some in my lounge as I have a dimmer switch that works off my TV remote and I didnt want to change it. They work exceedingly well, no flicker.

sorry just realized you said 12in crt, these wont be big enough, it has to be a 12.1" lcd or a 14in crt.

:)

sounds interesting, I think a 4:3 12.1" lcd translates as equivalent viewing area to a 14in crt. The only problem is the signal, which must sync to 25khz/55hz, unusual by anyone's standards! I dont mind trying one if they're cheap enough! :)

Ideally I want to gut a faulty CRT monitor and put an LCD panel inside the original case, along with any power supply and electronics. It's only a 14in tube.

A few years ago I used to be able to get a multisync adapter you could strap on the back of a VGA monitor and it gave you conversion from any legacy standard into VGA, dipswitch selectable TTL, analogue 75R, PAL, RGB, you name it. But the company is no longer trading.

 

Can anyone recommend a cheap converter? Source video is RGBHV TTL at 25khz/55hz. Nearly EGA but not quite.

I tried a GBS8200 as advertised on ebay and amazon which shows its EGA line frequency up to 25.5khz, but it's presumably faulty as it floods the screen with red once it's warmed up.