Closeup of the wiring. The circle on the left is the motor of the mechanical interruptor. The colorful wiring coming from the right side brings the power supply in. The empty vertical slot on the bottom-left is where another socket could be added for a fifth module.

The back of the 551C with the protective plastic plate removed. Everything is hand-wired. I don't know who chose to do all of the wiring in a SINGLE COLOR, but I hope none of it needs repaired! The terminations are mostly wire wrap posts.

These are the two 400D modules that came with the 551C. These provide all of the management functions for a single line, including hold functionality.

Closeup of the front of the 400D modules. One got smashed up in shipping, but they're cheap anyhow.

Closeup of the power supply. The low voltage fuses are pretty odd...a piece of phenolic with a bit of fuse wire in the center.

Ring supply in the usual operating position. Above it is an empty area where another module could be plugged in. There is no socket fitted currently.

With the 118A ring supply flipped up, you can see the mechanical interruptor below. The interruptor is responsible for the ring cadence (bells and lamps) and the "wink" cadence for 1A2 telephone lamps. You can also see that the ring supply plugs into the line with a stacking 3-prong plug, which makes it easy to use outside of the 551C.

Closeup of the ring supply. Unfortunately, the edge was damaged during shipment.

Cover off, as it came. The large box on the right side is the system power supply. To the left of that are the module sockets (two 400D modules installed) and the 66-type punchdown block. Below that is the ring supply (115 VAC at 30 Hz) and the mechanical interruptor (under the black ring supply).

The unit from the outside. This is a 551 C revision, so the case is plastic/fiberglass. Much lighter than the earlier steel revisions. The whole unit weighs a bit less than 20 pounds. It's about the size of a large shoebox.

Is spot logical, that is the question

Is spot logical, that is the question.

lp0 on fire city
Although yeah, I know it predates all that by decades. I really really want to go to bletchly museum next time I'm passing through the UK even more now. Thanks for posting.

Yes Halloween & 666 is sort of odd, but what's strange about the time? I've had a total come to $6.66 a few times & sometimes the cashier will gasp in horror. Just a number.

Aww.....  what a cute kitty.

yeah, he's pretty small

yeah, but its damn near impossible to get him still long enough for a picture!

is he ever awake? XD

good 'n clean

Ahh fair enough. Sounds like they didnt really know what they wanted in the first place (half the cat 5 going to the wrong place for example). Adding rack options would have turned it into a 5 day job, especially when the decided they wanted it moved half a foot to the left, or painted purple... Still, tidy install :-)

As a nw engineer, I always appreciate a tidy, well thought out installation - Ive been around too many spiders' web designs.

Why did your customer not fancy buying a wall mounted rack? Would have made the install and patching even more tasty imo.

they did not want to go into a closet because they did not want to lose closet space, so this is actually in where there office is going to be... they built a bunch of shelfs after everything pictured was mounted (the top shelf can be seen in the image with my hammer and punch down tool...

this was supposed to be a quick and easy job - i work for the VoIP provider... someone ran 1/2 the cat 5 wires from the desks in one office, but they ran them out of the office and down the hallway (exposed) but did not terminate them anywhere) so I had to pull those wires all back....

when all said and done, a job that was originally planned for about 1/2 day turned into a 3 day project...

oh.. back to your question.. i did not provide them with an option of a small rack because it is a small network (only 7 jacks, well port 12 in the panel goes to the fax jack) and the equipment that they have is not really rack mountable... and i felt that mounting a rack would take space away from the shelf unit that they wanted to install...

oh PS - I even labeled the patch cords according to the port #'s on the switch for easy troubleshooting in the future since the wires are tied up on the wall neatly...

As a nw engineer, I always appreciate a tidy, well thought out installation - Ive been around too many spiders' web designs.

Why did your customer not fancy buying a wall mounted rack? Would have made the install and patching even more tasty imo.

DAY 1:

Top Left: customer provided Linksys router (did not check model number)
Top Right: customer provided Linksys switch (did not check model number)
Middle left: PAP2 VoIP adapter for door phone
Bottom left: Viking RC2A relay for door phone
(underneath is a phone jack to connect a line cord from the RC2A to the PAP2, since the RC2A uses screw terminals for the dial tone input)
Bottom Right: 12 port CAT6 patch panel (the wiring is all CAT5, but my boss bought CAT6 panels in bulk accidentally)

DAY 1:

Top Left: customer provided Linksys router (did not check model number)
Top Right: customer provided Linksys switch (did not check model number)
Middle left: PAP2 VoIP adapter for door phone
Bottom left: Viking RC2A relay for door phone
(underneath is a phone jack to connect a line cord from the RC2A to the PAP2, since the RC2A uses screw terminals for the dial tone input)
Bottom Right: 12 port CAT6 patch panel (the wiring is all CAT5, but my boss bought CAT6 panels in bulk accidentally)

DAY 2:

Top Left: customer provided Linksys router (did not check model number)
Top Right: customer provided Linksys switch (did not check model number)
Middle left: PAP2 VoIP adapter for door phone
Bottom left: Viking RC2A relay for door phone
(underneath is a phone jack to connect a line cord from the RC2A to the PAP2, since the RC2A uses screw terminals for the dial tone input)
Bottom Right: 12 port CAT6 patch panel (the wiring is all CAT5, but my boss bought CAT6 panels in bulk accidentally)