[snip]
There was no other power source for the bell, and they needed to be loud enough to be heard a long way off.
The REN on my cordless phone is listed as 0.0B . It COULDN'T be drawing no current at all.
BTW, I now have phone from the cable company. I don't know it's REN capacity, but it's working for me with 2 "real" phones as well as the cordless and a 13-year-old DVR connected.
Or a diode or two are blown. That happened to an old (PCMCIA) modem of mine. Actually, it came that way. I used to carry a coupler and a reversing coupler when I traveled.
And back in the '60s, our Phone Company charged an extra $0.50 monthly fee for a lighted dial.
It could be an imperceptible amount if the ring detect circuit was a FET. The ringer itself runs off the wall wart or the battery.
The old system always had enough juice to run a few phones but the central office could tell how many bells you had connected if they looked. Back in the old "illegal phone" days people did not want them to know about the extra phone they stole. Ma Bell did not sell phones, they only rented them. Until the late 70s decision against ATT, it was a breach of contract to hook anything to a phone line without renting a DDA coupler from Ma.
OK silver satin, rib up, you have tabs all up, tabs all down, one up on one end, one up on the other end. That may only be 3 electrically
In those days a bridge rectifier was selenium, not silicon and about the size of 4 saltine crackers stacked with a quarter between each of them
In those days they charged that much for a longer handset cord.
It is a standard "feature" of phone cords that the tip-ring colors are swapped end-to-end. Look at the wire connections through the plastic plug. As a result a coupler, to connect 2 phone cords togetether, also has to do a swap (I just checked one to verify). (That is - "1-2-3-4" at one plug/jack is "4-3-2-1" at the other.)
Probably a TRS plug - tip, ring, sleeve.
In the good-old-days when phone connections were made through an operator switchboard with patch cords an extra wire was added to the subscriber pair at the central office. The extra wire was to determine whether the pair was already in use. All the operator jacks had to have connections for all 3 wires - tip, ring, sleeve. The control wire connected to the sleeve. The operator touched tip of the patch cord plug
- connected to their headset - to the end of the jack, the sleeve. If in use there was 48 volts (?) and the operator heard a click. Then lights were added for each jack. Mechanical switching centers also carried a
3rd wire at the central offices.
OK. I'm just stating the fact that it couldn't be exactly zero.
I wish I still had one of those phones. The ones you could get in any color you wanted as long as that was black.
I suppose most young people wouldn't know what to do with the dial.
Actually, my grandmother had a white one. The one that was around where she worked with porcelain and the (white) slip dripped on it.
IIRC, those things were really expensive. I don't quite remember when they were required. I remember when they (phone companies) SAID they were required and it was common to ignore the rule.
I had to read that a few times, but I think I understand that now.
You're using flat cable (not individual wires, so that factorial stuff is out).
You mention 2 variables (the position of each plug), leading to 4 combinations. There's another variable, you could turn the cable upside-down before attaching the plugs. These variables would seem to allow only 2 different cables (straight-through or reversed). where's the third one?
BTW, I'm reminded of the "combination logic gate" I built in college. It had 8 functions: AND, OR, NAND, NOR, X-NOR, X-OR, X-NAND, X-AND. The last 2 have on useful function, but they're still there.
[snip]
I've seen those old rectifiers. If a modern rectifier cost too much, I suppose that would too.
- Mark Lloyd
Did they really care? During the 60s I ran hundreds (thousands?) of ham radio phone patches using home brew equipment attached to the phone lines. Stateside we hams often CQed (called) other hams in cities that had relatives and used their phone patches to beat Ma Bell out of long distance charges. I also ran phone patches for service people overseas, mostly Viet Nam. I think the phone company was well aware but didn't really care unless we took down a line. They certainly never bothered me.
"0.0" is not exactly zero. It is less than 0.05, though.
I remember my grandmother saying the same sort of thing when she was forced to get her first dial telephone.
Sure, hams got around them for years. IIRC, there was a specific exemption for them (relay).
What they cared about is if you had more than one device and were not paying THEM for it.
Money-grabbers.
And good for 150ma - with incredibly high voltage drops. A 250 volt plate rectifier could drop as much as 50 volts, IIRC.
I still have 2 rotary dial phones here. The one in the garage was the original one from the phone company with my number in the dial. The other is a pay phone out in the tiki bar. My grand kids may not even know it is a phone.
It mostly applied to commercial installations. IBM designed and built a better modem than the Bell unit (faster and more reliable) but they were at a disadvantage because the customer still had to rent the coupler.
I had that problem at someone's house, the phone is "over there on the table" and I simply could not find it. Cordless thing, on a charge stand. Who'd have known?
Christopher A. Young Learn more about Jesus
I still have 2 rotary dial phones here. The one in the garage was the original one from the phone company with my number in the dial. The other is a pay phone out in the tiki bar. My grand kids may not even know it is a phone.
In 1969 I troubleshot a DEC modem that was in a rack, made from TTL logic. That was a production model with the PDP-8I series. I was a real data communication technician, whoopee. Still used a coupler.
Greg
After all these years, I just realized the ironic situation. Out of tech school I was offered two jobs. One at DEC, and one at ATT. I was destined to work on phone lines! That didn't last long, I got drafted.
Greg
Isn't it easier to just get a wireless snowblower and not have to worry about the electronics? [and where do I find one?
Jim
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