Panasonic 308 Easa-Phone questions

[gpo706]

Over here in the UK (and other countries who use the same GPO-type setup), the extensions on a 308 are numbered I think 20-27 or 21-28 (I can't recall it 100%, it's been a while!!), and the internal and external ringer cadences are the opposite, so 2 short rings for external and 1 long ring for internal...

If you loop-back one of the extensions (e.g. the "last" extension) to one of the CO ports, you can make the system ring as though it's receiving a call from outside the system, so it'll play the external ringer cadence from an internal call...  

That sounds quite mad!

So I could jump say-  ext 32 to 36 to the 5 free CO ports, and get a PBX jumping to the PBX?

Someone else on the forum ran a 616 to a "sub" 616 on an extension and it worked and didn't fry the CO line in!

Anyway my 616 rings the extensions in a cycle, so its a constant cacophony of differing rings, works a treat with three trimphones plugged in...

UK systems run from ext 21, 21 being primarily designated for the programming phone, and 22 for the DSS console.

And its 4 REN BTW, not 3 (unless the 308 is different).

[twocvbloke]

I got the idea from another forum, when discussing phone systems someone mentioned loop-backs, so, yeah, you can connect your 5 spare extensions to the 5 empty CO line ports...

Though really you only need to do one extension to one CO line to make it ring an "External call", though I think you can use the CO lines to act as an intercom between systems, I'm just not sure how...

[gpo706]

It's getting a bit mind-boggling 2CV.

In theory I can run 5 extensions to the 5 CO inputs and designate through the programming phone which rings to which CO line etc?

And maybe even a "sub" PBX?

The configurations seem exponential!

Anyway I just bought 5 x RJ11 to 431A sockets off the bay, and these are going to being like an equivalent to "patch cords".

[twocvbloke]

When you think about it, that's basically how they formed telephone exchanges, expanding and interconnecting Strowger selectors (originally intended to have a single digit for each subscriber) to add more and more number combinations, and there you have a telephone network...

Though my knowledge of it all stops at the loop-back stuff, cos I've not played in detail with such things...

[Sargeguy]

The 308 arrived today.  It powers up but other than that it doesn't do a heck of a lot.  No tone even when hooked up to the CO.  Can't call another phone.  Where exactly is the battery strap I pull to reset?

[Sargeguy]

OK it is now fully functional.  The problem was the rotary phones I was using.  I had a WE 306 and a 503 rigged with modular plugs. .  Both of these phones work on the land line but not when hooked up to the PBX. Most of my other phones are 4 prong or hardwired.   My only modular phones are manual wooden wall phones or candlestick desktands I have adapters around here somewhere.   I dug out my 1953 500 which had been modularized (I try not to think about it) and it works just fine.  I now have it hooked up ringing a 293A, a 333, a 533, a 251, and a 20-B in addition to a 500.  I need more modular cords of various lengths.

[Phonesrfun]

Sargeguy:

The reason your 306 and 503 phones will work on a land line and not on the Panasonic is simple, and easy to fix.

This tells me that your yellow and black wires from the modular cord are wired together inside the phone, which is a common practice, since the yellow and black wires are usually extra.  Just tape the ends of the yellow an black wires individually and let them dangle inside the phone or snip them off altogether.

The 308 uses the second (outer) pair which is yellow and black to provide power to the proprietary electronic phones when they are used.  By connecting a phone that has that pair shorted out to the 308, you are shorting out the power to the entire 308.

I have seen sellers on e-Bay connect the yellow and black wires together all the time, and normally that doesn't bother anything, but when they sell on e-bay the seller has NO idea that the buyer will have the same line configuration as the seller, and shorting the second pair can lead to a bad sale.

Besides the 308, there are some other ways the second pair are used:

• A second line coming into the house from the CO, I.E. a fax line
• A second line coming out of a VoIP ATA
• 6-volt AC power from a wall wart transformer to power a bulb in a Princess or Trimline phone

There could be other examples, so the best policy is just to snip the yellow and black off. 

[Sargeguy]

Thanks!