UK Vintage Radio Repair and Restoration Discussion Forum

UK Vintage Radio Repair and Restoration Discussion Forum (https://www.vintage-radio.net/forum/index.php)
-   Components and Circuits (https://www.vintage-radio.net/forum/forumdisplay.php?f=40)
-   -   What are these leggy things? (https://www.vintage-radio.net/forum/showthread.php?t=163796)

Uncle Bulgaria 11th Feb 2020 9:08 pm

What are these leggy things?
 
2 Attachment(s)
Adorable, but unknowable.

ms660 11th Feb 2020 9:21 pm

Re: What are these leggy things?
 
Thick film IC's.

Lawrence.

turretslug 11th Feb 2020 9:51 pm

Re: What are these leggy things?
 
Quote:

Originally Posted by Uncle Bulgaria (Post 1216411)
Adorable, but unknowable.

Maybe not- they look rather like Philips codes to me.

ajgriff 11th Feb 2020 10:07 pm

Re: What are these leggy things?
 
I think they're sometimes known as hybrid boards - a sort of SMD based module fitted as part of a piece of equipment mainly constructed with conventional discrete components. I have a Citronic PA/Disco amp (1980s?) which has them. It's in the 'might never get round to it' pile.

Alan

Outrun_uk 11th Feb 2020 10:10 pm

Re: What are these leggy things?
 
Thick film hybrid modules, purpose could be anything - they are pretty much manufacturer or device specific.

SiriusHardware 11th Feb 2020 10:22 pm

Re: What are these leggy things?
 
Looking around, the SAB3013 IC on the larger module is described as a
"D to A converter and analogue memory" (?).

Philips210 11th Feb 2020 10:27 pm

Re: What are these leggy things?
 
Quote:

Originally Posted by turretslug (Post 1216425)
they look rather like Philips codes to me.

Hi.

That's what I was wondering. The twelve digit code with four digits, space, three digits, space and five digits (4822 212 21513) definitely looks to be a Philips code. You very often see the 4822 XXX XXXXX codes in Philips service manual parts lists.
I also think, as others have pointed out, it's a type of thick film hybrid circuit.

Regards,
Symon.

EDIT: From a long time back, I may be wrong, but I recall the Philips KT4/K40 (System 4) used similar looking thick film modules on the microcontroller board particularly the one with frequency synthesis tuning (TRD IV).

Maarten 11th Feb 2020 11:00 pm

Re: What are these leggy things?
 
They're certainly made by Philips in their Krefeld factory (most or all thick film hybrids were made there). I think 1985 date codes, one has a Dutch factory 12NC and the other one a matching tail of such a 12NC, so most likely from a TV set. SAB3013 points to either a TV set or a VHS recorder, but a VHS part would carry an Austrian or German factory 12NC, not a Dutch one.

The 4822 service 12NC can indeed be looked up in service manuals. I'd start with the K40 manual.

dsergeant 12th Feb 2020 8:01 am

Re: What are these leggy things?
 
Yep, think film modules. Used to work on similar when I was at Ferranti, even remaking broken bond wires with a big machine and microscope.

Sideband 12th Feb 2020 10:16 am

Re: What are these leggy things?
 
My guess is probably from a Philips remote control panel. There were several types depending on the features of the TV.....TRD IV (that's TRD 4 for Tuning Remote Digital) and VST (Voltage Synthesis Tuning) both types used on the System 4 chassis (KT4, K40). Also possible (I think) on the slightly earlier K35 using TRD IV. I used to have a 22CS3850 using TRD tuning and I think that had thick films on the tuning board. It was a long time ago.....

G6Tanuki 12th Feb 2020 8:39 pm

Re: What are these leggy things?
 
There were a similar series of 'thick-film' modules by Philips/Mullard which were encapsulated in a light brown matt-finish goop - hence they were colloquially nicknamed 'biscuits'.

Usually with an "OM" part-number prefix - typically being HF/VHF/UHF gain-modules, used in plenty of Philips, Marconi 1980s/1990s professional instrumentation gear, and also in stuff like masthead preamps for UHF TVĀ·

They have not aged well.

kevinaston1 12th Feb 2020 11:06 pm

Re: What are these leggy things?
 
I Googled 127-02031 and am told they are from a Philips medical cardio vascular ultrasound uni

Maarten 14th Feb 2020 2:51 pm

Re: What are these leggy things?
 
That doesn't work as the cardiovascular thingy will have a part number starting with 4522 instead of 3122. The other digits have a higher than coincidental chance of being the same due to the way 12NCs are constructed.

Those are 99% sure from a tv set, very likely both from the same set, and there's a 90% chance that tv set has either a kt4 or a k40 chassis.

For those who are curious, this is the way it works for coding group 31, and at least partially for coding group 45 as well:
- Digit 1 and 2 indicate the code group, 31 for consumer electronics factory numbers
- Digit 3 and 4 indicate the coding centre which often but not always corresponds to a country, 22 for The Netherlands
- Digit 5 and 6 indicate the sub coding centre which often corresponds to the relevant design department. Sub coding centres often start counting at 10, so 12 is really common.
- Digit 7 an 8 indicate the article group, 70 is for assemblies in code group 31, possibly the same in code group 45 so that makes sense as well
- Digit 9, 10, 11 is an incremental designator, starts counting at 000 so 203 is also quite common as many article groups contain 203 or more articles.
- Digit 12 is the revision, starting at 1 so 1 is quite common but it can be disregarded anyway.

This system mostly doesn't apply to coding groups 48, 53 and anything from 82 up, and details are often different between groups.

The way the system is set up, means that within a production location, even only the last 5 digits are often sufficient for uniquely identifying a part especially if it is known what kind of part it is, but as soon as you step outside the location, things get really confusing quite fast. Years of observation and collecting numbers can lead to an accurate guess. Even people at Philips usually only know what they need to know.

Uncle Bulgaria 14th Feb 2020 3:35 pm

Re: What are these leggy things?
 
You guys....

Quite amazing the knowledge repository here.

So, the $64,000 question is: are they useful, or shall I just keep them for decoration? There's something of the lepidopterist in me and mounting them on card in a frame appeals.

I did various searches with different parameters online with the numbers, but didn't get anything, let alone a cardiovascular unit! They were off an old board of unknown provenance.

Maarten 14th Feb 2020 4:16 pm

Re: What are these leggy things?
 
Must have been a tuning/control board. The 4822 number should be in the service manual for the TV set/chassis.

For a TV collector they might be useful, but they don't go wrong that often and there aren't many sets left.

I suspect their decorative value may be higher than their actual value for repairs, so either is better than throwing them away.

Guest 14th Feb 2020 5:01 pm

Re: What are these leggy things?
 
Decoration, do a search for "Deep Picture Frames" and for a few quid, job done. They are a marvel of their era.

MotorBikeLes 14th Feb 2020 8:24 pm

Re: What are these leggy things?
 
Thorn used a couple of thick film units in the 4000 chassis. i had one for repair, a frame fault I think.I got a replacement and cured the fault, but curiosity got the better of me, so i dug bits of encapsulation away untill I was able to extricate the faulty item (a transistor possibly a resistor as well, long time ago) and I successfully soldered in replacements, fitted it and it worked OK. I then put the new one back in, keeping the repaired one "just in case".
They did not look the same as your two being fully encapsulated.
Les.

knobtwiddler 15th Feb 2020 11:10 pm

Re: What are these leggy things?
 
Quote:

Originally Posted by ajgriff (Post 1216432)
I think they're sometimes known as hybrid boards - a sort of SMD based module fitted as part of a piece of equipment mainly constructed with conventional discrete components. I have a Citronic PA/Disco amp (1980s?) which has them. It's in the 'might never get round to it' pile.

Alan

If you have a disco mixer which contains them, then they're most likely VCAs (e.g. for crossfaders) or RMS detectors (for compressor / limiters -or possibly level meters in the case of a PA power amp ).

The form of these modules is often seen in the audio world. They look a little like the opamps used in Studer tape machines (which would have far fewer components btw - but very similar construction).

I'm intrigued to read Citronic used modules like this, though. I would've thought it were cheaper to buy monolithic units from dbx etc...or maybe not? I guess the ICs weren't that cheap early on and some OEMs rolled their own.


All times are GMT +1. The time now is 10:09 am.

Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.