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 Tecnico 1140 what a bastard of a set
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 Return to top of page · Post #: 1 · Written at 8:28:50 AM on 24 July 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Actually it's not so bad once I became a contortionist lol. Valves upsidedown or on their sides. And getting the chassis out of the case. There is a missing sticker that advises to tune the set to 4QL before removing it from the case . That probably means the dial pointer won't get stuck and become a roadblock which it did for me. Then you have to stretch the speaker grill out so the switch shafts won't foul as well. A quick check revealed the speaker tranny was open circuit and thankfully I had a identical one I had pulled out of a trashed Philips chassis. It bolted right in and looks the part.
After doing a full recap it's performing quite nicely now. I will send photos soon. The case has a few stress cracks in it but I can't see them being a problem after a good Clean and treatment with Hydrogen Peroxide Cream.


 
 Return to top of page · Post #: 2 · Written at 3:49:28 PM on 27 July 2023.
Irext's avatar
 Location: Werribee South, VIC
 Member since 30 September 2016
 Member #: 1981
 Postcount: 482

I sympathise with you on that front.
The STC 538B I have just restored was a nightmare to work on.
Components are all on top of one another and the fear of breaking some irreplaceable part is ever present.


 
 Return to top of page · Post #: 3 · Written at 10:00:26 PM on 24 October 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

I finally got this set finished. A friend sent me a great 3D printed badge for it.

Tecnico Valve Radio
Tecnico Valve Radio
Tecnico Valve Radio
Tecnico Valve Radio


 
 Return to top of page · Post #: 4 · Written at 12:07:00 AM on 25 October 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

You young fella's seem to not realise that these things were rarely made with servicing in mind. They were actually in most cases built in layers. The enjoyable ones to fix (sic) are ones like a particular Stromberg Carlson, where they put three caps next to the chassis an then put the coil & switch box assy on top of them. On more than one, an RF coil has had to be removed to get at a dud bit further in.

One should have at least two haemostats but size matters. It is incredible as to what you can navigate in and out of tight places with them and what you can hold to solder or extract with them.

I work on the theory that I will get at least two to three sets in a year that will be absolute dogs. I have a now working (as best as) a set that once was a Battery set with 1K6 etc. and six tubes. Now its got five from the 40's in it like 6U7, 6V6. Wonderous mistakes like wire wound cathode resistors in the RF, missing decoupling and the usual feral caps & resistances.

Plus a few bits to try & sort out issues.

All part of the servicing game. Still nothing to beat the Airzone where the 6D6 envelope fell out of its base (not the socket) when the set was inverted: One fault less.


 
 Return to top of page · Post #: 5 · Written at 8:03:51 AM on 25 October 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Hey Marcc I love it when someone calls this 62 year old a young bloke LOL.
And photos have been sent.


 
 Return to top of page · Post #: 6 · Written at 9:20:35 AM on 25 October 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

And my next birthday is 72. I suspect you got into the game late & I started in the sixties.


 
 Return to top of page · Post #: 7 · Written at 8:27:49 PM on 26 October 2023.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7342

Photos uploaded to Post 3.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 8 · Written at 9:58:58 PM on 26 October 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

Hmm, I have a Technico that looks exactly like that one, apart from from being a bit beat up.

I don't recall anything tricky about it, although it's been a number of years since I've opened it.


 
 Return to top of page · Post #: 9 · Written at 8:16:31 AM on 27 October 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Robbert is yours the large one or the small one. This is the small one and it's very tedious even putting it back in the chassis. Most of them have broken badges because the metal speaker grill needs to be bent outwards for the knob shafts to clear it.


 
 Return to top of page · Post #: 10 · Written at 8:56:19 AM on 27 October 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

Need more detail with the shafts? These on potentiometers are either too short on the common ones and a damn nuisance if it's splined.

I just had a Lekmek with a 75mm shaft from front vs 45mm for the common std pot to replace it. That was merely a case (not unusual) of reducing the length of the new ones shaft with bolt cutters and turning an extension shaft out of Aluminium to sort it. Some times just a socket, utilising an offcut.

This just custom made for the set.

Lekmek control knob


 
 Return to top of page · Post #: 11 · Written at 11:09:40 AM on 27 October 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Marcc
this is a sealed set. The speaker grill is attached inside via two screws and washers ( it slides under them) . The only way I can dismantle or replace the grill is if it slides out from under the washers. This can mean a point of rattle which tends to annoy me LOL.
In future I would just modify the bit that goes under the washers and place a bead of pva glue at the top of the grill to prevent any future rattles. However the grill is originally installed in such a manner that the badge will break when pulling apart.
The knob shafts poke out about 3/4 of a inch past the grill which makes it impossible to remove the chassis without bending the grill.
If any of you would like a new badge then I can put you in touch with a fellow that makes them.


 
 Return to top of page · Post #: 12 · Written at 9:19:01 PM on 27 October 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

On working out how to get it apart, I would be considering what I had to do, to eliminate that little bit of treachery.


 
 Return to top of page · Post #: 13 · Written at 9:22:45 PM on 29 October 2023.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7342

Photo uploaded to Post 10.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 14 · Written at 10:11:44 PM on 29 October 2023.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

Robbert is yours the large one or the small one.

Finally got around to digging it out. Didn't know there were different sizes. This one is about 27.5cm high measured on the side.

It's got 4 knobs on the front unlike the 2 knobs on yours. Model number is 1050.


I removed a few screws off the bottom and lifted the plastic cover off, the valves are: 6BE6, 6BA6, 6AV6, 6V6GT, 5Y3GT.


There's a metal plate across the bottom which needs to be removed before being able to access the capacitors etc.

Otherwise, it looks conventional.


 
 Return to top of page · Post #: 15 · Written at 1:48:56 PM on 3 November 2023.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2161

Robbert I seem to remember you need some 2A5s

https://www.ebay.com.au/itm/115905748429


 
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