Author Topic: GPO 722 (aka the TRIMPHONE!)  (Read 16291 times)

Offline gpo706

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GPO 722 (aka the TRIMPHONE!)
« on: November 11, 2010, 12:12:12 PM »
I have one already for years, useless with handset crackle very bad, it looks two-tone green but it described as "blue" - go figure.

Anyway in my quest for a "Golden Shot" phone, I needed a "donor" set, so I bid on one was going cheap - went for 10.01, but then I was hedging my bets with ANOTHER one same colour in case the first one was snapped up last minute.

Of course it didn't so I ended up with two, same colour, so will see which one is better!

Second one was 2 pence cheaper at 9.99!

http://www.britishtelephones.com/t722.htm

Note the funny colour annotations, apparently these are 'Grey"

"now this should take five minutes, where's me screwdriver went now..?"

Offline bushman

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #1 on: November 11, 2010, 12:19:47 PM »
Is that considered a wall unit or a desktop?

Bushman

Offline AE_Collector

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #2 on: November 11, 2010, 12:31:08 PM »
Here's a question for you GPO...

Frequently when looking at British phones on ebaY they talk about it having been "converted" or "not". I see one of your trimphones comes complete with everything needed to make it work except the wall to mount the "socket" (jack) on.

Did the GPO use North American style jacks or those somewhat similar but different looking plugs that are slightly larger with about 6 pins all arranged in a row on one side of the plug/jack? I've seen these plugs on phones that people brought from Hong Kong when moving to Vancouver.

I also saw something somewhere about using pins 2 & 5 for the line rather than pins 3 & 4 like we do in North America. Assuming the pins are numbered in order they purpousely kept more seperation between the two line wires which is probably a good idea.

So...what does "converted" imply in ebaY listings? Converted to the current GPO standard plug using pins 2 & 5 (if that is the current standard) or converted to pins 3 & 4 with North AMerican standard plugs, or something else alltogether?

Terry

Offline gpo706

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #3 on: November 11, 2010, 05:40:50 PM »
Bushman:

"KIT 422A - WALL MOUNTING KIT
This consists of a plastic wedge shaped box (wall bracket), handset clip, cradle bar and a longer case retaining screw. To install, fit the bracket to the wall using the three securing holes.
The following modifications will have to be carried out to the telephone instrument:-

   1. Remove the four rubber feet on the underside of the instrument.
   2. Remove the existing line cord. The exchange line is then connected to the instrument via the hard wiring.
   3. The existing cradle bar may need to be replaced if it differs from the new cradle bar found in the Kit 422A. The exchange line cable should be brought into the wall bracket via the bottom, under the sloped back panel that contains the fitting instructions and behind the cable retainer which is situated as part of the top right-hand telephone support hook.

Once the cable has been routed as described the cable should be cut to length i.e. to the bottom edge of the wall bracket. Then strip the outer sheathing to approximately 50 mm below the support hook. Hang the instrument on the two support hooks of the wall bracket and clip the lower half into place to secure. Terminate the exchange line cable. Replace the telephone cover and place the handset clip in position then secure by using the longer case retaining screw."

On the link above, I have never seen one EVER!
"now this should take five minutes, where's me screwdriver went now..?"

Offline AE_Collector

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #4 on: November 11, 2010, 05:49:40 PM »
Must be a pretty big wedge as the trimphone looks to be quite wedge shaped already (in the wrong direction for wall mounting).

Terry


Offline Sargeguy

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #5 on: November 11, 2010, 05:50:23 PM »
That is one ugly phone :P  Are you sure it wasn't made in Bulgaria???
« Last Edit: November 11, 2010, 05:52:11 PM by Sargeguy »
Greg Sargeant
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Offline gpo706

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #6 on: November 11, 2010, 05:54:35 PM »
ae - "converted" means they have had the 4 wire spaded connections - 4 wire to 4 wire spaded, converted to 4 wire "PST" (Plug and socket) jacks aka BT 431A plugs.

http://www.telephonesuk.co.uk/wiring_info.htm

http://www.telephonesuk.co.uk/line_jacks.htm

Theres plenty phones on the bay un-converted can be re-wired with a 4 spade to 431A plug for less than 5 quid, or you could buy a old style 4 wire terminal block (soapdish) , wire the phone to the block and then the block to the socket to a new cord.

Links above cover most everything.
« Last Edit: November 11, 2010, 06:02:18 PM by gpo706 »
"now this should take five minutes, where's me screwdriver went now..?"

Offline gpo706

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #7 on: November 11, 2010, 05:57:13 PM »
That is one ugly phone :P  Are you sure it wasn't made in Bulgaria???

Sargeguy, best not plan on any holidays here soon, its considered a design classic here!

They are still making repros today.

Back in the day it was the only alternative to the 706/746 series and you paid a premium rental for one of these - if you had a trimphone you were quite well off!
« Last Edit: November 11, 2010, 06:01:25 PM by gpo706 »
"now this should take five minutes, where's me screwdriver went now..?"

Offline Sargeguy

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #8 on: November 11, 2010, 06:02:11 PM »
Well, it is...interesting.  Maybe I'd like it more if looking at it didn't make me dizzy.   :-\.  Seriously I'm glad you found it and good luck with it!
« Last Edit: November 11, 2010, 06:05:04 PM by Sargeguy »
Greg Sargeant
Providence, RI
TCI /ATCA #4409

Offline gpo706

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #9 on: November 11, 2010, 06:10:08 PM »
Sargeguy - the biggest problem with Trimphones is their weight, it slides round the table if you stand up, you need Blu-Tack to secure them to a surface, or duct-tape, or concrete.

On the positive side it has a radiation emitting numberplate and a 3  tone ringer, in fact it escalates the sound from soft to loud depending on how many rings it takes.
"now this should take five minutes, where's me screwdriver went now..?"

Offline gpo706

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #10 on: November 11, 2010, 06:39:41 PM »
Here's a slidy one:

http://www.youtube.com/watch?v=tPtHDFE0SQQ&feature=related

Here's a ringing one (warbling one):

http://www.youtube.com/watch?v=Yx03gDhV6-8&feature=related

This covers the history of the 706/746 and the Trimphone, very good info on this:

http://www.youtube.com/watch?v=aF5QuL5ooQI
"now this should take five minutes, where's me screwdriver went now..?"

Offline paul-f

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #11 on: November 11, 2010, 07:52:21 PM »
That is one ugly phone :P  Are you sure it wasn't made in Bulgaria???

IMHO, They're actually quite attractive in person.  I know, there's no accounting for taste.  They also come in a variety of color combinations and the previously discussed leather covered models.

  http://www.classicrotaryphones.com/forum/index.php?topic=3105.msg41534#msg41534
Visit: paul-f.com         WE 500  Design_Line

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Offline McHeath

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #12 on: November 14, 2010, 01:35:38 AM »
I like the look of the Trimphone, rather a 60's affair and I like the design of that era.  Though I know that style is in the eye of the beholder. 

Never seen one in person, only on the web or in a few Brit shows they pop up once in a while.  Seems like there was one in one of the Men in Black movies as well, but I might be off there. 

Offline elmwood

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #13 on: November 16, 2010, 01:01:25 AM »
That is one ugly phone :P  Are you sure it wasn't made in Bulgaria???

The European phones look more like products of their times.  For example, if they were designed in the 1970s, they look very 1970s to my eyes.  By comparison, North American phones from the 1950s through the 1980s have a more timeless appeal about them.

Still, I'd like to have one of the 1970s-era Dutch or GPO phones.  The design would be an interesting contrast to my Craftsman and contemporary furniture, and it would look percect in an IKEA-furnished guest bedroom.

Offline gpo706

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Re: GPO 722 (aka the TRIMPHONE!)
« Reply #14 on: November 19, 2010, 07:18:48 PM »
Elmwood: a trimphone is the perfect accessory for a retro "batchelor pad" - groovy!

The first one came yesterday, and I was too knackered after work to do much except take it apart and see whats what and how much of a clean it needed.

Its not actually very manky  a light clean and polish should do the trick, well apart from the original line-cord which was filthy and the loops distended, but I had bought a new remanufacted replcaement, so out with the old screwdriver and get going.

Now Trimphone linecords are strange GPO cords as they have smaller grommets at the phone end and standard square ones at the line end (like the 700-series, square at both ends).

They also have from the phone end, about 6ft of straight cord which transforms into coiled cord up to the terminal block, hence the replacement, as I had already predicted it would be filthy or stretched.

Do any US/European phones have this arrangement?

Obviously these "hybrid" line cords are take advantage of the light weight of the design to encourage "roaming" around your pad.

So I stripped the old one out and put the replacement in, and dials fine, then put the case back on and nothing!

Now turns out the phone end of the linecord has a rectangular shaped grommet which I had put in the wrong way (no instructions online or in the manuals) so how was I to know it was lifting the PCB which it sits under and also acts a cord restraint - you loosen it prise it up and insert the cable, then screw back down, it  clamps the ends of the 4 spade connectors.

So I had it standing slightly proud when the case was back on, which stopped the "reversed hookswitch" from touching the switch.

So having rectified the line in cord, the case goes back on again, - nothing.

Now it turns out the new line cord has very long wires to the spade connectors, longer than the originals, so were snagging the hook mechanism, so a tidy up and loop round the case screw staunchion and dials fine again,

Now ring through the PBX, looks at the wiring again, I forgot the 3.3k resistor across T4 to 5, another fiddly job, that added now it rings that unique Trimphone warble.

Case back on and all is well, except the progressively louder ringtone doesn't work its either hardly audible on "soft" or shrill on "loud".

Another thing nobody tells is the "medium" setting marked by an arrow on the three position dial, you need to select this to get the progressively louder warble...

What a palaver as usual, still it was a fairly easy couple of hours to get it working and warbling again, no crackle on the acoustic horn either.

One lives and learns, just needs a decent spruce up, Part 2 when the next one arrives.

Can't make out the date on the base, its rubbed off, the case is dated 1981, thought that could be a new case on a rufurb.

« Last Edit: November 19, 2010, 07:30:49 PM by gpo706 »
"now this should take five minutes, where's me screwdriver went now..?"