Aurora converter news

[ppppenguin]

There has been some recent speculation about the Aurora SCRF standards converters which many of us use. I have been in touch with Darryl and can report:

Demand for converters has fallen. He thinks this is not really due to lack of interest in vintage TV overall, simply that most of us who need converters now have what we need.

There is no problem with availability of the major parts. He holds a good stock of the modulator chips and the Xilinx FPGA is still available. The only trouble is the industry-wide shortage of surface mount capacitors and resistors. This has forced up prices, assuming you can get them at all. https://epsnews.com/2018/05/23/electroni...shortages/

Stocks of SCRF converters are currently very low. Darryl will be making another batch shortly. Beyond that it very much depends on the rate at which that batch sells.

[Murphyv310]

Hi.
Probably inevitable, saturation point has no doubt been reached with existing collectors, with new blood coming to the interest at a low point. We still see the odd older person taking up the interest but a dire lack of interest from young people.

[`FRANK.C]

I got my Aurora in 2007 and it has worked perfectly ever since. Darryl builds them old style(to last) and that is the problem. The modern way appears to be to build to a (low)standard that way there is a constant stream of return customers. I think the best chance of a Aurora needing to be replaced is if the owner cant find it.

I would never have thought that passives could be in short supply.

Frank

[ppppenguin]

It's happened before. In the .com boom all sorts of parts went on short supply. But usually it's chips, such as memory, that go on short supply.

I don't have full records of Aurora faults but the ones I can remember are:

Lazy crystal (not yet proven, it's coming to me soon to fix)
Faulty F connector. Astonishing. A bit of metal embedded in the insulation that shorted it out after a while in service
Badly soldered Xilinx. one pin was slightly bent during assembly. Worked on test, failed with customer.
Faulty decoder chip. Worked on test, failed with customer.
Customer error (wrong power connector). They made a decent donation to the Vintage Wireless Museum as an apology for wasting our time

[Murphyv310]

There was a mod that I did to one of mine for noise on sound, I believe it was either a SM cap or resistor, the memory isn't as good but it was a cure.
Have three but passed on another 4 to customers bought directly and through Crowthorne. All though have been reliable including my old multistandard version.

[ppppenguin]

I'd forgotten about the resistor tolerancing problem that affected some of one batch of Auroras. I think it was something to do with an aspect of the modulator chips not being well documented and which Darryl used in a slightly non-standard way.

[ppppenguin]

I also forgot about the one with fried input termination resistors. Somebody had somehow made a video source with about +5V of DC offset. This will certainly fry the input 75R termination. It's actually a pair of resistors that give 75R but the effect is the same.

After I found and fixed the fault he fessed up to what he'd done. I think we agreed on a £20 donation to the VIntage Wireless Museum.

I now have the unit with the suspected lazy xtal on the bench. It worked perfectly of course, even when starting from fridge temperature. At freezer temperature the xtal was still running but the analogue output seemed to be in trouble. Similarly if I use freezer spray on the analogue output area. I will investigate further.

Tomorrow I should be getting a unit where the report is "no output". I'm keeping an open mind on that one but have a fairly strong feeling it might be user error.

Yet another one is due to be brought to me in person soon. With a fault described as looking like intermittent twitch on line hold. This has been reliably witnessed (John Wakely) and I have no idea at all as to what might be causing it.

[`FRANK.C]

Hi Jeffrey
Sooner you than me. The components are really tiny and very densely packed.
Us Aurora users are lucky you are around.

Frank

[ppppenguin]

Strange fault. When I was squirting freezer around the analogue output circuits I was actually freezing the main 3.3V voltage regulator which is pulling down its "power good" output when cold. This is connected so that the Xilinx reboots. Not sure if the reg itself is faulty or something else is wrong. I'm in touch with Darryl who is helping me through all this.

[ppppenguin]

While I'm pretty sure the regualtor isn't 100% right, I can't readily get a suitable part in the UK unless I buy a strip of 50. (Surface mount SOT25, 3.3V, with power good output on pin 4)

Adding a 1K pullup from the power good pin to 3.3V seems to make it proof against freezing so that's probably what I'll do.

The 2nd Aurora arrived this morning. Works perfectly. It's what we politely call "user error". The owner doesn't use computers at all so won't see this He's also looking for somebody to fix another 405 TV. Ideally within 30 miles or so of Lancing, West Sussex. Any thoughts? As a request for a service this really belong in another section but I'm not sure where. Do we have a section fo rthis? Do we have any kind of register of people doing this?

PS:
ISTR a guy know as Mark Pirate or some similar name in the Worthing area who might do repiars. I don't have contact details for him. Can anyone help please.