|
Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
|
Thread Tools |
18th Jun 2018, 10:18 am | #1 |
Banned
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 3,897
|
What is this please?
Found in a junk box at the auction.
Built on a McMurdo International Octal base. Contains a transformer, 2 PCBs, and a Ferrox cube core with a slug tuner. Seems to have 1 transistor and a few resistors. Marked "1000 c/s" so assumed some sort of oscillator? |
18th Jun 2018, 11:27 am | #2 |
Dekatron
Join Date: Nov 2011
Location: Surrey, UK.
Posts: 4,400
|
Re: What is this please?
"Oscillator" was my first thought, too, but maybe an alternative is a sharp 1kHz active AF filter? Is enough discernible through the dragonfly-in-amber treatment to work out the circuit and base connection? I see that CV2389 was supposedly the first CV designation applied to a transistor, so implying around mid-fifties, perhaps similar to the OC71 etc.
|
18th Jun 2018, 1:00 pm | #3 |
Banned
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 3,897
|
Re: What is this please?
Trying to work the circuit out is very difficult, the components are on and between 2 paxolin boards, point to point wired, not PCBs.
There are 6 leads visible on the iron cored transformer, ( may be more onto the pins), 6 on the ferrite tuned transformer, 3 resistors,470,2K,56 ohms, 2 ceramic caps,and the transistor CV2389. |
18th Jun 2018, 3:00 pm | #4 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,902
|
Re: What is this please?
Oscillator is a possibility, but I'm inclined to suspect it's a tone decoder.
David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done |
18th Jun 2018, 4:06 pm | #5 |
Nonode
Join Date: May 2007
Location: Preston, Lancashire, UK.
Posts: 2,511
|
Re: What is this please?
I have one of those! I've always thought it was a Post Office part. I'll dig it out and see if it has any identifying numbers.
|
18th Jun 2018, 11:13 pm | #6 |
Heptode
Join Date: Apr 2009
Location: Scratby, Norfolk, UK.
Posts: 651
|
Re: What is this please?
Hi
Is this any help? Kind regards Dave |
20th Jun 2018, 5:23 pm | #7 |
Rest in Peace
Join Date: Feb 2004
Location: Hexham, Northumberland, UK.
Posts: 2,234
|
Re: What is this please?
I would say it could be a plug in tone decoder. The coil will be tuned to a particular frequency, probably audio, and either pass or reject depending on design. I used to work on Motorola equipment which employed plug-ins to decode in-band audio frequency sequences, although yours seem to be a good deal earlier than the ones I have seen.
Alan. |
21st Jun 2018, 12:02 am | #8 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,902
|
Re: What is this please?
The earlier generation tone decoders were vibrating reed devices.
David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done |
21st Jun 2018, 9:11 pm | #9 |
Rest in Peace
Join Date: Feb 2004
Location: Hexham, Northumberland, UK.
Posts: 2,234
|
Re: What is this please?
I think the old radio control systems also used tuned reeds. It's a long time ago now...
Alan. |