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Wiring up a Trimline

Started by andy1702, June 05, 2019, 04:03:29 PM

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andy1702

So I bought my first Trimline, which is no mean feat here in the UK!
Actually, it's technically a european 'Gondola', which is a Trimline in everything but name.

My problem is wiring it up, especially for the oddball UK system with 3 wires and the capacitor in the wall socket. It's complicated even further by the colours of the conductors in the line cord, which are green,brown and white and are of no standard I've ever seen before.

Having a sneaky peak inside, brown goes to L1 and white goes to L2, which I assume are the line connections. However green, which I initially thought went to T1 next to them, actually goes right up the other end of the phone and disappears into a mass of wires I haven't disturbed yet. It's another green wire that comes back and goes to T1. You'll see in one of the photos below I've got the green wire in the line cord connected up in my temporary lash-up test, but I've now disconnected the green ijn the line cord as I don't know where it goes in the phone yet. Interestingly it works perfectly though, so I guess I got the brown and the white right.

Incidentally, ignore the colours I've connected to in the white cord. It's a modified BT extension that I chopped the socket off one end, so the conductors are not the normal standard colours.

Having done a bit of reading about converting US phones for the UK, it seems most people just use the two line connections and do away with the (normally blue) anti-tinkle third connection. So I think that's exactly what I'm going to do here.

The one thing that doesn't seem to work though is the LED that lights the dial. I was surprised to find this is red.Does anyone know where I should be looking to give a clue about repairing the LED?

Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.

dsk


Is it any wiring diagram inside the phone?
It is probably a way, just leave it with no converting.  The UK system is actually good, but since "you" always make your own standards you will always get problems with adapters etc. The genius ring wiring of your power system with fused plugs, fantastic, but no one else does that. :)

Regarding the LED, it is possible that the third wire was used to an external power source, and if ringing power has been tried there, it may have blown a component.

If it is only one LED you could probably take power from the line.

If the third wire is not in use just connect that to the ringer instead of one of the wires to the ringer, and use that for the ringer wire. switch L1 and L2 in the other end if it does not ring.  Do not care about the capacitor.


dsk




dsk

1 step forward, the red led is powered by the telephone line: https://www.youtube.com/watch?v=CCEJC6R97cs
dsk

Jack Ryan

Is there a LED?

I've only had a few Gondolas but none had a LED. Also, although the case looks like a US Trimline, the components are different.

Perhaps there are a lot of different Gondolas.

Jack

jsowers

I agree with Jack about this not looking at all like a Trimline on the inside. Could one of the mods change this to "Wiring up a Gondola" instead? It would help someone else find it if they had the same problem.

Have you tried reversing the polarity of L1 and L2 to the phone to see if that makes the LED light? In the YouTube video that DSK posted, it does indeed look like a red LED in that it flickers when you dial. Incandescent would never flicker like that, being supplied by a second power source.
Jonathan

andy1702

It's definitely an LED, not a bulb. It sits inside a clear plastic part of the dial which acts as a light-pipe to light tie figures in the dial from the inside out.

I've seen some photos of the inside of trimlines that look similar to this one, but definitely not all of them. I wonder if there were a lot of different versions over time or if the photos I've seen have been misidentified?
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.

dsk

I have never seen this version. I realy like the ringer.

Jack Ryan

Quote from: dsk on June 07, 2019, 09:34:30 AM
I have never seen this version. I realy like the ringer.

The ringer is one of Mix and Genest's contributions to the ITT group.

Jack

andy1702

I thought the ringer was quite clever.

Looking into it a bit further it seems the handset is very similar to a true Trimline but the base is totally different.
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.

HowardPgh

It looks like the trimline but the network is in the base rather than in the handset.  Is this a South American phone?
Howard

Jack Ryan

Quote from: HowardPgh on June 07, 2019, 04:58:00 PM
Is this a South American phone?

Made by ITT in Spain and distributed widely.

Jack

dsk

Anybody having the schematics?

dsk

andy1702

Quote from: dsk on June 08, 2019, 03:43:55 AM
Anybody having the schematics?

dsk

There was nothing inside this one unfortunately  :(
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.