Advice from a do-it-yourselfer

Installing & Living with a Home Phone System

by Chris Arndt


The following material originally appeared in the online KX-T Digest.

Chris discusses his experiences with an analog KX-T123211D system, but most of this will be very useful for anyone contemplating the do-it-yourself installation of any of our phone systems, in either a business or home environment. It's also good background for anyone having a system installed by others, and for anyone who already has a Panasonic system.

There are five sections:


Three years ago we started planning and owner/building a new 2800 sq. ft. single-story house. We wired it for phone, video, audio, alarm, and other stuff. We have lived here now for two years. We did all the wiring and system programming ourselves. We have a Panasonic KX-T123211D KSU configured for 4 CO lines, 32 extensions, and two doorphones. I have experience only with the Panasonic, but I'm sure most of this applies to any small phone system.

Until I installed the Panasonic, my phone system experience was limited to hooking up extensions, and dialing the phone. I bought the Panasonic based on the recommendation of a friend in the business. I've never been disappointed in its performance. (Andy Rooney mode on) Have you ever noticed that when you get a new (to you) car, you start looking at them on the road? It's the same with phone systems. As soon as we got the Panasonic, I started looking at phones everywhere I went. Bottom line....I like the looks of the Panasonic feature phones the best, especially in a home setting. (mode off)

Modern hybrid phone systems are programmable in a bewildering number of ways. You can specify which extensions ring on which incoming (CO) lines, which extensions can dial out, and on what CO lines, feature phones have buttons that can show when another extension is off the hook, you can page through feature phones, and/or a separate amplifier, prohibit dialing certain prefixes or area codes, and set up system wide speed dial numbers, and even more than I can list here. You can change it based on time of day, too. Most features are available from a standard phone, also.

Your first impulse may be to add up the number of rooms you might like to have a phone and use that as a basis for system size. Hmmm, eight rooms, eight extensions ought to be about right.

However, a home phone system changes the way you look at extensions aroundthe house in a big way, for several reasons.

One is that now you have the ability to put all those cool phone line devices on a separate extension, so you can use then around the house.Alarm dialers, answering machines, X-10 responders, modems, faxes, voicemail boxes, other interfaces all can have their own place now.

Another is that with a phone system, you can call around in the house to places where you might want an intercom, say basement or garage. We have extensions everywhere ( garage, deck, master bath, vanity, etc), and were surprised at how much they do get used.

The most important reason, at least here, is that the programmability solves some problems having the system itself creates, but at the expense of using another extension. For example, we use a door phone as a doorbell. The visitor pushes the button, and the phones in the house ring in a special cadence. Well, I set up my answering machine on my desk as an extension, and it started answering the door when we weren't home (really confused the UPS guy!). So now you need an extension at the desk that can answer the doorphone, among others (may as well put a cool feature phone here), and a separate one for the answering machine.

We were going to put in a six-CO line, 16-extension KSU, but got a good deal on a 1232. I'm glad we did the 1232. We are over 16 extensions, now.

Bottom line, if you can afford it, put in a KSU twice the size as what
you thought you needed. You'll probably use it.

Part 1: Wiring

We owner-built our new house, so we had the luxury (?) of being able to do a lot of the work ourselves, cutting costs and ensuring that things
were as we wanted them.

For the phone system, we wired the whole house with PVC jacketed, unshielded, 6-pair, twisted pair cable. I think we used about 1500 feet of it.

The Panasonic analog 7130 feature phones use 3 pairs if you want the off-hook call announce (OHCA) to work, so the 6 pair cable left us with a full spare home-run at each jack location for expansion. It's pretty likely you will wind up wanting more than one extension at one or more jacks, for answering machines, FAX, modems, novelty phones or ??.

Another consideration is that while the KSU will work with all standard phones (plus one feature phone for programming), I guarantee that once you start using the feature phones, you'll want them in more places.

We installed single-gang nail-up plastic boxes everywhere we wanted a jack, and then ran the 6 pair from each back to wire closet (called a
"home-run"). Pay attention to the height of any boxes for wall phones. I put ours in about 4 inches too low on the kitchen backsplash and in a couple other locations.

At this point it's very important to label each end at the time you pull it in, so you can sort it all out later. We have 30 or 40 6-pair cables coming into the wire closet. If they weren't labeled, it would be a real
nightmare looking for a particular end. I have found a couple that didn't get labeled, and I still don't know where one of them goes.

Sanford Sharpie markers are indelible on the grey cable jacket, or you can use one of the several cable label systems available. Avoid stuff like masking tape. It's my experience that the adhesive on some tapes reacts with the jacket and makes a gooey mess.

If you are doing this yourself (and maybe even if you are paying for it) put jacks everywhere you think you might possibly want a phone sometime. We put at least 2 jacks on opposite walls in most rooms, one on most outside walls (for the deck, and to run into the motorhome), in the master bath, and by the separate vanity, in the garage, for the doorphone, etc. When you are done, any unused locations can be covered with a blank plate when the house is finished.

Wire is cheap. Make sure you leave plenty of extra on each run in the wire closet, and maybe 9-12 inches at each box.)

About the only thing I might have done differently: Our house is single story and rather long, with the wiring closet at one end. I could have saved some time and labor if I'd pulled one run of 25 pair from the wire closet to a central location and brought the station runs to to that point. One 25 pair cable will support 8 3 pair feature phones, or up to 25 single pair extensions.

Part 2: Connecting

So now we have a bunch of wires hanging in the wire closet or phone room, and it's time to set up the equipment.

Installations vary at this point. We had one big (BIG, 10" diameter) bundle of wire coming through a hole in the ceiling at the back of the wire closet, a room about 8' x 9' with one door and no windows. It contained phone, video, audio, alarm and some other wires in it. I elected to build a false wall covered with 1/2" plywood out from the back wall and one side wall. This provided a chase to hide all the wires, and a set of panels to mount stuff on. Really looks nice when I get all the panels on.

The Panasonic KX-T 123211D is mounted to the false wall, and the phone wires come out through a hole cut in the false wall. This particular KSU uses standard 50-pin Amphenol connectors for the extensions, and RJ-11 jacks for the CO lines. Others may use other connectors, mainly all RJ-11 jacks. I mounted 4 standard 66-blocks on the wall (one for each 8 extensions possible in the KSU) and punched down 25 pair pigtails with Amphenol connectors on them to interface to the KSU. Incoming CO lines are terminated in RJ-11surface jacks.

Make sure you leave room for all the connecting hardware, plus access to the KSU, when you mount it. It also needs a clean source of AC power. (Don't put it on the same circuit with your table saw!) The 1232 is 19" h x 15" w x 7.5" d. Our installation takes up about 3' x 3' on the wall, and is a little congested. If I did it over again, I'd allow more room. Depending on what you add now or later, you might leave extra room on the wall and/or space for a shelf.

Now, when I want to hook up an extension, I locate the correct cable in the bundle, strip off the jacket, and punch it down on the appropriate 6 pins for the extension number I want to hook it to. At the other end, hook it to an appropriate jack, usually a 6 pin modular wall plate, and plug in the phone.

Four- and 6-pin jacks can be had in single and dual wall plates, wall phone plates, surface mount, exterior wall plates with a water proof cover, and several "systems" that sell separate wall plates with up to 6 cutouts, and snap in jacks for phones, BNC connectors for networking, F connectors for CATV, fiber SMAs, and probably others I don't know about. I have made up plates I couldn't find locally from pieces of other jacks.

As you lay out your extensions, pay attention to the KSU instructions. The 1232 defaults the first 2 extensions to the first 2 CO lines in a power failure, so you would not be totally without phones in a blackout.

You would want to put these in the most appropriate locations, maybe the bedroom or kitchen.

(The Panasonics, and I suppose most systems, allow for backup power of some sort. We have ours on batteries. Plugging it into a UPS would work for a short time. Depending on use, the 1232 will run for 12-18 hours on two 12-volt, 12-amp hour gelcells.)

Part 3: Programming

The most daunting thing to me about putting this system in ourselves was the stack of programming manuals that came with the 1232. The main book is almost a half inch thick, plus a couple of update addenda and such. I read those at night for a long time figuring out what it all meant.

Programming requires one feature phone plugged into extension 101.

The best news is that it'll all work right out of the box. If you have stuff like door phones and answering machines and multiple CO lines it may not work perfectly, but it will work. The easiest way to approach all the programming hooey is to ignore most of it, and only learn what you need to know to fix the immediate conflicts.

Once that is done, you can move on to refining the system for whatever niceties you like. After I figured that out, everything went pretty smoothly, and now when I add a new extension or device, I know what programming I will have to do for it (although I usually miss something the first try.)

Just about any feature of the system is programmable. CO lines can appear or not appear on any extension, they can ring or not, and have dial-out access or not. Same thing with doorphones. Feature phone buttons can be programmed to be speed dial keys or DSS (direct station select) keys. DSS not only works as a speed dial for another extension, it also shows if that extension is in use on another call.

Modem and FAX extensions can be programmed for data line security, so no one inadvertently breaks in on your Internet session. Voicemail integration using in-band signaling is available. 100 system wide speed dial numbers can be programmed, and the numbers kept from appearing on the LCD display of a feature phone if security is needed. If you have door phones, door opener contacts are optional, also, if you have an electric door strike. You can also exclude prefixes and I think area codes from being dialed. This is just a sample of the programming available.

Most programming can be different for day mode and night mode. The modes can be switched by the phone at ext 101, or programmed to switch on clock time. You could use this to keep a teen phone from ringing after 9 PM, and keep 'em from dialing out, too. We use it for other things, as I will talk about in the next installment.

Different programming is available at each extension. The DSS buttons mentioned above are station specific. Each 7130 phone (and other models) has an auto answer button. Pressing this will make the phone answer itself in speakerphone mode for any intercom call (not a CO line). This is pretty handy in rooms where you might have your hands full or wet, like the kitchen or laundry. You could even use this as a baby monitor, but probably wouldn't want to activate this feature in the master bedroom. :-)

Extensions can be locked with a DTMF code to prevent outgoing calls. Extensions can be grouped for ringing and paging (could page both kids rooms without disturbing the rest of the house). There are also other options that are probably not of much use in a home setting. Off-premise extension cards, DSS boxes (busy lamp fields), and DISA (direct inward system access) cards are some of them. As I stated before, we did add the battery backup to ours. A DSS box might be cool, too. Call parking is probably of little use in the house, but doing your own conference calls is nice, whether between COs or a CO and another extension

One feature I have not tried yet is computer programming of the switch. It has a serial port on it for interfacing to a printer or computer. I think all of the tedious programming you do with the feature phone on ext 101 can be done quicker with a computer and a comm program. You might be able to dump the programming to a file for reupload in event of a crash.

You can dump the current programming to a serial printer for archiving.

Part 4: Tricks & treats

Well, Let's see. So far in this series, we have selected a phone system
wired for it, installed it and programmed it so that it functions OK.

Now comes the fun part, figuring out how to make it perform, maybe in ways not imagined by the manufacturer.

One of the first things I said about sizing was to allow for extra telephone line devices and expansion. Let's see what that means in our case:

We bought a 1232 set up as a 4 CO, 16 extension KSU. It's currently configured for 8 CO, 32 extensions (I got a good deal on a 4 CO card for a backup). It has the door phone and door strike adapters in it, also.

There are currently three incoming CO lines. A fourth will be an auto answer, auto-dial adapter to my cell phone.

We have phones in the kitchen counter area, kitchen desk, by the country kitchen couch, laundry room, wire closet, living room, master bedroom, vanity, master bath, guest room, 2 offices, garage and outbuilding. There are wired jacks on the deck (three -- it's a big deck), and by the motorhome parking, and a separate cordless phone for outside that works over most of our ten acres. That's 19 extensions (well, 20, one office has a second extension for a novelty phone). Of these, 9 are 7130 feature phones, 5 are standard phones, and 2 are novelty phones, plus the cordless (FWIW, the novelty phones are teddy bear speaker phones. The mouth and eyes move as the other person talks).

Beside the phones, we have the following telephone "devices": X-10 server (built out of an Apple II+), amateur radio autopatch, remote amateur radio controller, modem, alarm dialer, Melco Remote Access Unit, and three extensions for a voicemail box. There are nine more extensions, total of 29, leaving four spares right now. The X-10 server answers its extension with a synthesized voice, and accepts DTMF to control any of 10 housecodes, any unit. It's like having a huge X-10 control box at any phone, even the cordless.

The Melco requires some explanation. CO line 3 goes to a FAX/Modem switch prior to the KSU. Fax calls are routed to the FAX without going through the KSU. Another port on the FAX switch (switched on a DTMF code after the switch answers) routes to the Melco. NonFAX, non-routed calls go out a third port to CO line 3 on the KSU.

When a call is routed to the Melco unit, it answers and presents a dial
tone. After receiving a valid DTMF security code, it switches the call to an extension on the KSU that gives _internal_ house dial tone. Now the authenticated caller has full access to the KSU, and can call individual extension, page, or dial 9 and dial back out. Note that 'til now, no phone has rung in the house, but the caller has access to the system. I use this to check voicemail, among other things, without disturbing anyone at home. I can also call the X-10 controller, or any other device.

The Melco is like a DISA card, but I already had the Melco when we moved in.


Trick Time:

One extension is looped back around into a spare CO line input. Dialing this rings all the phones in the house just as an outside line would. We use this as a "house" phone, to call the other person when we don't know where they are. It is also useful when we are allowing other outside calls to go to voicemail, or calling in on the patch.

As I said, we just added a voicemail box, a 386 with a 4 line Rhetorex card that I got a great deal on used. We use it as voicemail, with all the VM bells and whistles (menus, remote notification, message waiting lamps, dial through, etc). We also use it, with the night mode on the KSU, as a wrong number filter after 9 PM. Living in a small college town, we seem to have a problem with late night wrong numbers, especially in the fall. After hours, incoming calls go straight to voicemail, and the last instruction on the menu allows for dial through to the house phone extension/CO line in case of emergencies. Works great at nap time, too.

The 1232 has a music on hold (MOH) input. 7130s allow MOH to be broadcast through the speakerphone speaker when the phone is on hook, by pressing the '1' key. I hooked the MOH input to a weather radio, so forecasts are available at any feature phone with the press of a button. It's amazing the positive comments we get about it from the people that do get put on hold.

The serial port on the 1232 will log outside call data (not intercom) to a serial printer. I use an old Epson MX-80 and a serial/parallel converter. By accident, I discovered that the 1232 will buffer up to a page of calls, so I have the printer on an X-10 module that turns on once a day for a few minutes to print the call data and then turn off. The data logged includes the extension, CO line, number dialed if outgoing, date, time, and duration. If you program the switch for account codes, it'll log them, too. This would be dandy for monitoring the kids calls.

I had a question in email about distinctive ring. If you put the door box on the incoming CO line before the KSU, you could plug the decoded ring jacks into different CO line inputs on the KSU, and treat incoming calls as separate lines.

Caller ID was another question. I believe some switches handle it now, but not the analog 1232. A CID box on the CO line before the KSU will show the data, but it wouldn't show up on a feature phone display.

There is a door phone option for up to two door phones, with an associated door strike actuator option. We use one door phone as a doorbell, and the associated strike relay to control the garage door. The second door phone, and strike relay will be for the electric gate, when we get it built. The relay closure is a few seconds long, and could be used for another push button control if desired. I used it for an X-10 alarm interface module for a while.


Part 5: Voicemail

We started out with our two old answering machines, and they did fine for a couple of years. Mine had message forwarding, but it would only dial one number, so I had to reset it a lot. As the machines wore out, I started looking at alternatives. I borrowed a Bogen Friday. It did some stuff I wanted, but the integration into the Panasonic wasn't that great.

I started looking at voicemail boxes. A typical voicemail box is a
standalone PC 386 or 486 (some 286es) with proprietary software and either Rhetorex or Dialogic interface cards. They are sized by:
Number of ports, or phone lines (2 to 16 or more)
Number of mailboxes (100 to 1000 or more)
Number of HOURS of messages, menus, and prompts the hard drive will hold. Ten hours is about the minimum these days)

A new 4-port, 10 hour machine starts at $3500 or so. I found new 2-port 10-hour ones for $2400 ($1950 if you can get it direct from the mfr). There are also companies that sell software and/or cards for real DIYers.

We wound up with a used 4 port, 10 hour, 200 mailbox VSR 200 for $1500. It has all the regular VM stuff...multiple menus and menu trees, auto attendant, notification to up to 10 numbers, broadcast to multiple boxes, day, night, and holiday hours. It integrates with the Panasonic, and accepts in band signaling, and will work the message waiting lights on feature phones.

We've only had it a couple of months, but it has become a really useful tool. Along with answering the phone, which the machines did, we use menus to direct people to information we could never squeeze onto a 30 second tape, like my wife's office hours and number for clients that call the house. I use it to tell people that are looking for the last company that had the FAX line number that they have gone out of business. Soon, I'm going to add an information menu and mailbox for my amateur television repeater project. It'll also do surveying, but I haven't explored that yet.

I mentioned the main application a few articles ago. After 9 PM, the phone system switches to night mode, and the voicemail to night menus. No phone in the house rings on outside calls, all calls go to voice mail. The last voicemail message are instructions on how to contact us in an emergency. All the caller does is press 0 and stay on the line. The box forwards the call to our "house phone" extension that is looped back to a CO line and rings all to phones in the house. To date, no one has needed to use the dial around. (I did test it a couple times.) Every couple of days I check the activity printout, and this has saved us a couple rude awakenings so far.

Intentionally left off of our menus, but still functional is dial through. When you programming the various menu responses, DTMF digits are assigned functions, so the box knows that, say, when a 2 is pressed, it should send the call straight to my voicemail box 1 is programmed as "first digit" which tells the box that our extension numbers begin with 1. This means that dialing an extension number during a menu will forward the call straight to the extension. We did not mention dial through on the menu messaging to avoid hassles from random button pushers, but we can still use it ourselves.



(1) Having a phone system at home is a whole different process than having a CO line or two and a bunch of extensions, and if you're not careful, you'll get an undersized system. I almost did.

I was going for a 616, thinking that we'd never fill it in our new house. After all, we really only have about 8 rooms, not counting baths. However, even though you can parallel a couple of phones on an extension, this is not necessarily the best thing to do.

Case in point... here at my desk is a 7130 with all 3 lines on it. Across the room is an answering machine. Same extension, right? Wrong for a couple of reasons. The biggest one is the door phone. I had to put the machine on a separate extension, and exclude the door phone from ringing it, else if we weren't home people at the door wound up listening to my answering machine message, and being very puzzled. (which brings up an interesting idea of having a dedicated machine for the door. :-) )

Anyway, I got a great deal on a 1232, and we are well over 16 extensions on it, and growing.

(2) I am an amateur radio operator. One extension is a radio/telephone interface device called an autopatch. I wired one door strike contact to the garage door. Now, from any phone in the house, the cordless, or my handheld, I can open or close the garage door. This comes in handy when I come home in my work truck.

(3) I put an old scanner tuned to the local NOAA weather station on for music on hold. Not only is it a conversation piece when someone is placed on hold, but (the main reason I did it) every 7130 in the house now is a weather radio. Just poke 1 for "background music" and there is the latest forecast.