Doug's SxS Switch   
Current Progress   Dec 2003 - Jan 2004   Feb 2004 - April 2004    May 2004 - Aug 2004   Sept 2004 - Dec 2004

Jan 2005 - Jan 2008

15 January 2005 -- Not much physical work has taken place on the switch itself lately, but I have been looking into what I need to interface my switch to Voice Over IP, or VoIP.  Several "switchers" (folks with electro-mechanical telephone switches like myself) are proposing the establishment of a private VoIP network wherein stations on one old switch can dial to a station on someone else's switch, with the intermediary link taking place on VoIP thus avoiding long distance charges and so on.  It would be very nearly like "real" CO switching and a pretty neat way of tying our old switches together into a network.

The proposal is based around the Linux-based Asterisk open source PBX, so I have been working on the configuration of a computer to run Linux and then load up and compile the Asterisk software.  So far I have had some problems with the version of Linux I tried since it appears to not include all the modules needed to successfully compile the PBX software.  At this writing I am downloading a later version of Linux to try.  I was successful, however, in finding on eBay a very affordable trunk card for the Asterisk PBX and have it already in hand.  I still need a station card and I am on the lookout for one of those, too.

19 January 2005 -- There's been some progress in the VoIP project.  I have managed (with a lot of help from other switchers) to configure a Linux machine with the Asterisk software and it is working, at least as a standalone PBX at the moment.  Connected to a station port on my step switch, I can dial to it from another step switch station and the automated Asterisk lady answers.  Currently it is not connected to nor configured for the switchers' network though I am working with that aspect at the moment.  I am a complete neophyte with Linux and the simplest tasks aren't because I don't know the commands.

In other news, I noticed this evening that my web pages went back to November's revisions.  Looks like Verizon had to revert to an old backup or something.  As a result, if you looked at this page earlier today it probably only went to late November.  Ditto for my stained glass page, which I also had to reload the latest rev this evening.

21 January 2005 -- Major progress in the VoIP project!  Last night one of the phone collector/switchers was able to dial in to my step switch and call an extension off same!  It was very cool.  There was a little bug that had come to light in the .conf files that were provided, but it required only a minor change and a restart of my Asterisk system and the next attempt to trunk into my switch worked perfectly.  The switcher and I had a nice chat and the audio quality of the VoIP connection was amazing -- I was expecting audio akin to the rotten audio quality of digital cell phones.

My system is not quite ready for prime time as there is still twiddling and tweaking needed, not to mention needing a permanent location for installation of my Asterisk PBX!  However, there is now proof of concept for this "switchers' network" as I was apparently the first switcher to get online with this new system.  Other switchers have expressed interest/desire to get into this so the next few months could be quite exciting.

23 January 2005 -- More tweaking on the VoIP system over the last few days.  My Asterisk setup is now available off the "CNET" (Collectors' Net) with a dynamic update of my IP address going on and all that.

Last night another switcher and I explored the use of the FireFly soft phone client software and we found that with that client a user can dial into an Asterisk machine remotely and in my case trunk into my switch.  Very cool.

The tweaking continues.  We discovered last night that FireFly crashes when you attempt to dial into a "milliwatt" 1000 Hz test number in my Asterisk machine.  Still trying to figure that one out.

30 January 2005 -- The VoIP integration project continues.  I received this week a Sipura SPA-2000 ATA unit to hopefully allow stations on my switch to be able to dial out onto the "CNET."  It took a day or two (or three!) of configuration playing to get everything just right in both the Sipura unit and my Asterisk PBX, but it eventually all came together -- and again with help from another switcher.

Yesterday I received a box lot of dialers that I purchased on eBay that will convert dial pulses to DTMF ("Touch Tones") since the Sipura SPA-2000 will only accept DTMF signals from a telephone set.  There were eight dialers in the lot however only two actually work.  Oh well, live and learn or something like that.  Again with some assistance I was able to configure the two working dialers to accept rotary dial pulses from an older phone and pass them out as DTMF to the Sipura box, which in turn is homed on my Asterisk machine which sets up the call and send it out over the network.  Pretty neat.

Now I need to build up another trunk board for my step switch so I can tie this dialer/Sipura mess to a selector level on my switch to enable any station attached to my switch to dial out on the CNET.   This is a rather exciting project marrying old and new technology together, and in the last few days a few more collectors have gotten their switches online in the CNET.

6 February 2005 -- Wired up another two-port trunk board and installed it on the switch and got it wired into the "1" level of the selectors.  Punched through some wire pairs up to the computer room and hooked up the new trunks to the Sipura/pulse converter mess and I now have full outbound capability from any step switch station into the CNET!  Things are a bit tentative in regard to the installation of the computer stuff for the VoIP aspect of the step switch, what with wires here & there about the computer area.  I know how I want to arrange everything, it's just a matter of getting the connectivity (network and trunks to the switch) in the right place and terminated nicely and all that.  I'll post photos of the VoIP pieces when I get things presentable.

10 February 2005 -- A nasty water main break over near work has work closed today so I took the opportunity of "found time" to neaten up the Asterisk PBX installation and its connections to the step switch.  First, I mounted the Sipura ATA box and Mitel Smart-1 dialer unit behind my computer desk, pictured at left.  The Sipura SPA-2000 is the small gray box, and the Mitel Smart-1 dialer is the black box to the left.  These items could actually be mounted just about anywhere, including near the switch, but my thinking is to keep all the computer-related stuff by my main computer and Internet and network connections.  Wiring behind the computer desk was connected to the outgoing trunks on the switch as well as a step switch station line.

The Asterisk PBX machine was placed next to my computer desk and hooked into the network and the step switch line for the incoming calls.  The machine is pictured at right and has an old WE500 sitting atop it which is plugged into one of the outgoing FXS ports on the Sipura ATA.  It is my "console" telephone of sorts to be able to test outgoing VoIP calls.

19 February 2005 -- Worked out a vexing problem with the step switch and VoIP interfaces.  I had a weird problem where if I used DTMF ("Touch Tone") to dial out on a VoIP trunk, the switches would perform correctly but drop the connection as soon as it selected the trunk into the VoIP ATA, as if the calling station had hung up, which it hadn't.  The line finder, seeing the station off-hook, would jump to life again and search for the line and return dial tone from the first selector again.  Sometimes dialing the VoIP trunk again would result in the selector successfully seizing a VoIP trunk, and sometimes it wouldn't.  If I used a rotary phone, everything worked fine.  After trying different variables in the equation I finally came to the conclusion that the holding bridge on the DTMF-to-pulse converter on the switch paths was loading down the line to the VoIP box too much so that there wasn't enough current for the "A" relay in the selector to hold the switch train.  The solution, or at least a work-around, was to wire the trunks to the Sipura box over at the second-to-last and last terminals on the "1" level so that by the time the selector hunts/rotates over there the holding bridge in the DTMF/pulse converter had dropped out.  That holding time isn't adjustable, unfortunately, and a better solution would be more current available from the Sipura box, but that isn't adjustable, either.  However the problem has been worked around and now DTMF stations can dial out successfully on VoIP.

Pictured at left is the rear sleeve & line termination panel on the switch and the VoIP trunk board is on the left edge, just above the small punch block and screw terminal blocks.

13 March -- Rather slow progress on the switch of late.  Too many other things going on.  Today, however, I did pull another 25-pr cable from the IDF by the switch to the house MDF so I can connect more lines from the switch to stations about the house.  Until today I had only 50 pairs going between the switch and the house MDF and those were completely taken up by the stations currently wired in and working on the switch, as well as things like the trunk feeds for the house CO line, FXS ports from the VoIP system, etc.  Since I still have another 20 lines' worth of line & cutoff relays to add to the switch, I needed at least that many more pairs between the switch & the house frame.

In VoIP news, folks on the CNET continue to call into my system from time to time trying out either messages in the Asterisk machine or listening to progress tones on the step switch.

29 March -- No step switch improvements to report, but an interesting VoIP/Step Switch interface item to talk about.  A soft phone client like Firefly can be configured as an authenticated client to an Asterisk machine so that it can appear as an extension on the Asterisk PBX.  Over the Easter weekend I went visiting to a friend's house 300 miles away, and on arrival there I was able to start up my laptop with configured Firefly client and through my friend's wireless access point and broadband Internet access I was able to dial into the step switch back home to report my safe arrival to the folks back home.  Likewise, the folks at home could call me at my friend's on my Firefly client from a step switch station at home.  I had previously built up an interface so I could plug in an older "G" style handset to the microphone and speaker ports on the laptop for use with Firefly, and it worked very well on my trip -- and no long distance charges!

3 April -- Started connecting installation cables to the last plate of line & cutoff relays.  Once those are hooked up then this last plate can be bolted to and wired into the switch.

Chased out a problem on one of the station lines this week.  It was noticed a couple of weeks ago that a station that worked just fine when its plate of L/CO was installed on the switch was no longer working.  One could dial to the station and it would ring and cut through, but going off hook to initiate a call from this line would result in a dead line.  Some closer inspection of the line & cutoff relays for this line resulted in finding some debris caught in the leaf of one of the relay switches.  Some gentle "surgery" was performed and the debris was removed and the station in question came back to life.

5 April -- Finished wiring in the last plate of line & cutoff relays.  Yesterday the plate was bolted to the switch frame and the first ten lines' worth of relays was connected and then tonight the last ten were hooked up.  There are now 80 dialable stations on the switch.  One line has a broken line relay, but that line has been permanently busied out so that folks dialing in from the CNET have a busy line to dial to so the busy tone can be heard.  It is most gratifying to have a significant portion of the switch now built.  Things on the yet-to-do list include a release battery alarm, all circuits busy tone, and quite possibly hooking up the reverting ring selector I have.

7 May -- Not much happening on the step switch in the last month or so, too many other things going on with work and ham radio stuff and so on.  I have, though, been working with an aspiring CNET member in the last few days on his Asterisk installation.  He has some older PBX-like equipment that he is planning to put on the CNET.

11 June -- Switch progress has pretty much ground to a halt, which probably comes as no surprise to the regulars readers of this page.  There are far too many other things going on around here lately, not the least of which was ham radio activities over two successive weekends, good weather finally showing up so all the outside tasks start beckoning, and the fever pitch that is the close-out of school ramping up to full throttle all leaving little energy at the end of the day for adding to the switch project.

The CNET, however, is alive and well and calls continue to come into the switch setup here from others on the network.  The new CNET member referred to in the last entry is now up & on the network and we have had several lengthy calls through our respective setups discussing all things telephonic.

12 July -- Had a nice surprise late last week.  Another reader of these pages sent me an AE connector, it would appear.   Haven't had a chance as of this writing to test it, but the switch is complete with a contact bank... perfect for the portable switch I keep threatening to make!  Many thanks, Don!

27 July -- I've made a short video of the switch in operation. It's a 15 second snippet made with a web cam so it's not the greatest overall quality, but heck it's better than nothing.  Click here to go to the video page.   On the page it explains what you will see and there will be a link to the video.

In other switch news, the AE connector I received a couple of weeks ago appears to be a party line connector as it contains a "minor switch",a small step switch, which receives a third dialed digit to select the desired party on a multiple party line.  Should be a fun one to get up & running!

18 August -- Did a few switch related tasks today.  First I painted the covers of the last two line and cutoff relay plates I installed earlier in the spring.  See the photo above to see the difference between the painted ones (left) and the banged-up as-found covers.

Also got to messing about with the AE party line connector received a few weeks ago.  I don't have the full hookup information for it so I don't have it operating in its entirety yet, but I can get it to step vertically, horizontally and then the minor switch in the top steps and everything resets when I hang up.  The switch needed some attention to some of the big leaf switches in it, and it needed a shaft spring (thank heavens for eBay!) but appears to be otherwise complete and working.  Now I just need some more accurate hookup information for it!

2 September -- Yesterday I connected about 15 more station lines through from the switch frame over to the house MDF so I can start thinking seriously about installing and displaying some other interesting phones about the house that are not currently hooked up any where.

Big news on the CNET today!  A few weeks ago a gent in the UK learned of the CNET through this page and contacted me by email.   It turns out he has his own very impressive step switch and he expressed an interest in Asterisk and perhaps linking his British Strowger switch into the CNET.  Today that event is closer to becoming a reality!  He has his Asterisk machine up and running and is tweaking the configuration files and was able to dial into my switch!  We had a brief chat and I rang him back on the line he has currently working.  There are a number of issues that he has to work out in his setup, but he's pretty close to being fully online with the first overseas switch on the CNET. Congrats, Jon!

23 October -- Pretty quiet on the switch project of late (no surprise to regular readers!).  Nothing new added to the switch itself though another station or two has been added to it in the house and tweaks of the Asterisk tandem into the switch are more or less ongoing.  I am presently configuing an Asterisk machine to work as an automated attendant and voice mail machine at work but it will have "hooks" into the CNET so I can easily play step switch from work.

27 October -- Got some more goodies in the mail from a step switch fan ... yesterday received a WE 30200 selector and a WE 33014 line finder.  Thanks again, Don!  Now I don't really have much of an excuse to not get started on the portable demo switch I have been talking about for a while...

9 November -- Through eBay I purchased another digit absorbing selector for the switch and it arrived late this afternoon.  The switch already has a DA selector in one of the paths, but not in both.  This 30976 selector turned up the other day and I got it.  At this writing I just got through testing it on the bench and it appears to work correctly.  It is set up for a very different dial plan than is on my switch so I will have to make those adjustments, but after getting it configured and installed on my step switch I can implement four-digit dialing.  The plan is to have a leading '3' in front of the existing three-digit numbers.

13 November -- Installed the 30976 digit absorbing selector on the switch frame today.  All station numbers can now be dialed with four digits, as well as the original three.  The incoming dial plan from VoIP on the Asterisk machine has been modified accordingly and now all VoIP calls that trunk into the switch are dialed as four digits ... almost like Long Distance calls arriving at the old CDOs!

1 December -- The broadband connection here went out sometime early on 25 November.  As of this writing it is still not back on and a lineman is scheduled to come by here tomorrow.  As a result my SxS switch and Asterisk system have been offline.  Any online work this past week has been done through "borrowed" wireless connections from neighbors on my laptop, and just this evening I got the modem going in my recently-upgraded-to-XP desktop system so I can use a friend's dial-up account.  Hopefully I'll be back online with the broadband connection in the next day or so.

11 December -- The step switch has been back on the CNET VoIP network for about a week now.  The recovery from the broadband outage was really something.  The connection was restored on 2 December, but it took three more days to get my router and modem talking to one another well enough again so the VoIP stuff would work properly.  It finally came down to the DSL modem being in the wrong mode, which I never had to change before, and the routers I was trying of course didn't want to work properly.  Everything was finally working again as before the outage by the evening of 5 December.  Computers!

7 January 2006 -- My VoIP system was offline for a few days this past week when I had to reset my broadband equipment and my IP address could no longer update correctly with the service I had been using.  I registered with another provider of this service and after the necessary changes were made in the CNET ENUM server, I was back online.

In other CNET news, another European switch is ramping up to join the network.  A gent in the Netherlands is in the testing phase of his Asterisk system and has been placing calls to various CNET members' switches, including mine.  This will make two UK switches and one NL switch (with another enthusiast being homed off the NL machine) on the CNET in addition to the North American installations.

14 January 2006 -- Today I put together a small peg counter for my switch.  A peg counter is a device that keeps track of calls on a switching device.  In my case I wired the counters to the selectors which conveniently have an output for just this sort of task.  When a call is dialed to the next working switch the selector puts a momentary ground on a supervisory lead.  That lead goes back to the counter.

The box and counters are recycled from some sort of timing device that had some CMOS logic chips and three 12-volt resettable mechanical counters.  The counter box is in my upstairs work room so I can keep track remotely of the call attempts on the switch.  The left and center counters keep track of the selectors in the first and second call paths, respectively, and at the moment the third counter on the right is not connected to anything.  I am thinking that I might want to hook it up to count answered calls on the switch but at the moment there doesn't appear to be a convenient supervisory pin on the connectors to provide this information, so I will have to make up some additional circuitry to track that.

5 February 2006 -- I finally completed and installed the fuse panel that I started who knows how long ago.  I think it's been over a year.  Also on the panel is a circuit that I got from another switcher that is a relay-based flip flop circuit.  I have wired that in to the line finders on the switch so that succeeding calls are alternated back and forth between the two finders, instead of almost every call attempt going through the first line finder.  In a way, this circuit is an allotter, like would be used on Automatic Electric step gear.  The circuit works well, and the two panel mounted lamps on the left side of the fuse panel are part of the circuit.

22 April -- Not unsurprisingly, there hasn't been much of anything new happening with my switch.  A few weeks back I did do some experimenting with multiple tone generation in a PIC chip, in an attempt to provide original sounding progress tones on the switch.  That is proving to be not as easy as once thought.  What I should probably do is keep a lookout on eBay and the phone club ads for a real telco tone generator.  Meanwhile I will keep puttering with the chip method.

In CNET news, traffic from the CNET into my switch has dropped off quite a bit.  I guess the novelty of dialing into other switchers' switches has worn off, though I try to dial into some of the other systems a couple of times a week.   There are still new folks ramping up to join the network.  I spoke with one such switcher on the PSTN earlier this week, he has a basement full of switch gear that he is looking to get online.  Then there was today where another switcher was talking about his newly acquired step and crossbar PBXs and how they will be on the CNET soon.   Neat stuff.

20 July -- Wow, it's been a long time since I have updated this page, though it's also been a long time since I have done any messing about with the step switch -- other than using it!  Today I did some experimenting with coupling audio into the ring supply to eventually be able to inject a ringback tone on the switch.  It didn't go too well.  Apparently I need a LOT of audio to drive the coupling circuit.  "Oh dear, back to the electronic brain" ...

23 July -- Finally built up a release battery alarm circuit for the switch.  Sort of had to...  While installing a new phone display in the house the other day and the requisite testing that goes with that, the one line finder jammed on release -- with power to the release magnet constantly applied.  Fortunately I went to see why I suddenly didn't have two paths on the switch.  This is why switches should have these alarm circuits on them.

Right, so that bumped the release battery alarm project up to the top of the list!  As of this writing the circuit is built and has been tested on the bench, now it is awaiting installation on the switch.  Only thing, though, is that this circuit is currently set up for a manual reset, and when it is tripped it removes the power to the release magnets on the switches.  Fine, that's what it should do, but the circuit powers up needing to be manually reset, so any power glitches will render the switch inoperable.  Now I need an adjunct power-up-reset circuit for the release battery alarm!  Forunately the power is pretty stable here so it shouldn't be too big of a problem until I come up with the reset-on-power-up circuit.  Main thing now is to get the circuit installed on the switch.

26 October -- Oh my; it's been forever since this has been last updated!  Built up but still haven't installed the release battery alarm... just too many things going on around here.  Had an interesting adventure last week when the area was hit with a major (and very early) snow storm, which put 16 inches of wet, heavy snow into the still fully leafed trees, which brought branches, limbs and entire trees down.  That created lots of utility outages and my location here was without commercial power for eight days -- which meant the switch and my Asterisk tandem were down for the duration.  My PSTN line and DSL remained operational, but the computer stuff could only be done, of course, when the generator was running or I hooked stuff up to an inverter and car battery.  We're still cleaning up the back yard here so there isn't much time or energy for phone projects at the moment.

I did, however, over the summer purchase some digital audio recording chips with the thought of creating some progress tone generators for the switch using authentic recordings of old switches, or decently re-created ones.  I have a very nice old dial tone sound that was created by another phone enthusiast on his computer and I would like to get that project rolling.

21 November -- Nothing new in progress on the switch to report, but did have a visit from a fellow switcher over the weekend.  Always nice to share switch talk with others and show off the handiwork on my switch.

CNET traffic still continues to come into the switch.  Mostly all test calls to the RNA or busied out lines, but still it's some traffic on the machine.  I likewise dial others' switches from time to time.

18 February 2007 -- Been a while again since the last entry, and the first entry of the new year.  Yesterday I completed the IDF at the step switch to the MDF of the house by running the last 25-pr cable between them.  I did have 75 pairs between the two frames, but what with the various auxiliary circuits going between the switch and the MDF of the house, in addition to the station lines from the switch, there weren't enough pairs to go around.  Once this latest 25-pr cable was pulled, the last 15 stations from the switch were connected to it and are now available at the house MDF for whenever I am hooking up a new station.

I was also having some problems last night and today with the switch going down.  The switch is plugged into the same GFI-protected circuit for the outside outlets of the house and with all the snow and melting snow we have at the moment, water was dripping on the plug and outlet for one of the roof eave heaters and causing the GFI to trip.  Did some remedial work on that today to protect the outlet from the melting snow so that should hopefully keep the switch operating!

3 March 2007 -- Finally hooked up the no such level/all circuits busy circuit in the selectors on the switch.  Dialing a non-existant level on a selector yields a 120 IPM tone.  At the moment it's a 400 Hz tone, but will hopefully be something more realistic whenever I get the digital recording chip project going.  Had a round of emails with the electronics parts vendor this week about my very delayed order which contains some of the external components I will need for building the recorder chip circuit.

17 March 2007 -- Started working with the digital recording chip project for providing old progress tones on the switch.  Preliminary tests show that this will likely work well.  The chips can be put into a loop mode where it plays over and over again.  Before I worked with the chips I was afraid of the noise that might be made as the chip cycled around back to the beginning, but it turns out this is not a problem; there is very little noise or "pop" as the chip loops back to the beginning of the recording, thus giving one a virtually continuous tone supply.

The problem, if you can call it that, is that there isn't enough drive from the recording chip to feed the dial tone or ringback tone input of the switch.  The dial tone is barely audible.  An intermidate amplifier is going to be needed.

However, enough about the practicality of the project is known to go ahead with building up a perf board with the chips on it and look into modifying the microcontroller program to supply interrupter lines to gate a chip to pulse the dial tone at the appropriate cadences for busy tone and reorder.

25 March 2007 -- Had another test of the "old" dial tone project today.  Turns out drive level isn't a problem; in my previous test I was connecting a lead in the wrong place!  I have modified the code in the PIC 16F84 chip to also provide 60 IPM and 120 IPM outputs to be used with an audio gating circuit to provide busy and reorder tones, respectively, from the old dial tone source.  The old dial tone is 600/120 Hz and is recorded as a 10-second sample in one of the ISD digital recorder chips.  The ISD chip is wired for continuous looped output of the recording.  Combined with the gating circuit, I have a steady output for dial tone, tone interrupted at 60 IPM for busy tone, and tone gated at 120 IPM for recorder.

The breadboarded circuit was connected temporarily to the switch this afternoon and an announcement made on the CNET mailing list which alerted folks to try out the new tones, albeit temporarily.  Now a more permanent circuit board definitely needs to be wired up and integrated with the existing microcontroller board on the switch.

5 May 2007 -- Received an interesting package from a web page reader this week -- thanks, Paul!!  I am in possession of a small shelf section with some switches, namely a selector, two outgoing repeating trunk plates, and a connector.  Apparently in a previous life this was a demo switch of some kind.  I have been wanting to assemble a portable demonstration switch for some time now and this will make the perfect base for just that sort of switch.  The shelf section will hold up to four switches or other apparatus.

The thinking at the moment is to configure the demo switch with a line finder, a selector and a connector, perhaps using a party line connector (I have a couple in stock!), which could increase the number of lines that could be configured.

Some planning in the engineering of the switch will be needed to connectorize everything so that the switches can be easily installed or removed from the frame to transport it because this old switch stuff is pretty heavy.  The unit as pictured weighs in excess of 70 lbs.

18 August 2007 -- Finally wired up a circuit board for the old dial tone project, tested back in March.  The project also required a firmware change in the PIC microcontroller, which was completed some time back.  Last night I pulled off the plate on which the microcontroller board mounts and installed a second transformer for the reorder tone coupling, as well as getting the uP board unattached as there were a couple of wires to connect to that board that interface to the recorder chip board.

The project was not without some hassles, I managed to blow two of the gates in the 4066 chip on the recorder board -- still trying to figure out what I did -- that gate the dial tone for busy tone and reorder.  Fortunately the other two gates on the chip are OK so a last-minute rewire of that circuit was in order since I had no other 4066 chips on hand, at least that I could find!  Once everything was hooked up and tested, it was announced to the CNET mailing list and several members have already checked out the "new" tones on the switch.

The mounting of the uP and recorder boards needs to be engineered so they are just laying in front of the switch at the moment.  The uP board previously mounted flat on the one panel but I need additional room to accommodate the recorder board.  I need to make some brackets so I can mount the boards on end.  Once everything is mounted in a "workman-like manner" I'll post a pic or two.

27 October 2007 -- Another long stretch without an update.  Still haven't properly mounted the "authentic tones" board, but I may be tackling that today. Just too many things going on, plus the weather has been unseasonably warm and nice throughout the autumn and who wants to hole up in the basement when it's so nice outside?  I also want to replace the 48V linear supply on the switch with a switching supply I bought recently.  I just took some current readings on the switch and have found (as I suspected) that the standby power drain for the switch is around 50 watts!  That translates to about 1.2 kWh a day, and basically means it's costing a bit of money to run the switch.  Standby current on the switching supply is around 10 watts.  I think the project for this weekend is to install the switching supply on the switch and then mount the tone and interrupter boards.

[later same day] -- ARRRGH!  In hooking up the new switching supply, a connection was reversed and the authentic tone board's components were fried.  Fortunately the microcontroller/interrupter board was spared so the switch still functions.  For now, (until replacement chips can be obtained) the switch is back to the micro-generated 200Hz/400Hz tones.  So much for the electricity savings, probably the year's worth of savings is lost with having to get new recording chips.  ARRGH.

4 November 2007 -- The replacement chips for the authentic tone board came in through the week and I was able to get everything going again yesterday.  I found during further testing that only the dial tone recorder/playback chip was damaged, the other recorder/playback chip on the board for the as-yet-unimplemented ringback tone was OK.

Now, though, I am noticing that the line finders (I think) are playing up on me, when you go off hook there's sometimes a definite pause between the LF seizing the calling line and the application of dial tone.  Both LFs seem to be doing it, at times.  Might be a problem in my DT circuit.  Have to play with it some more to nail down the problem.  Always something...

21 January 2008 -- Good heavens, but it's been forever since I've done an update!  Probably because there hasn't been much to talk about.  The holidays and life in general just gets in the way of the hobby stuff.

There is a little news, though.  A couple of months back I found an eBayer who was selling the little AE plates of L/CO like I wanted to use on my switch all along, and he had them at a decent price.  I purchased two plates and intend to wire them into the switch so that all 100 lines in my "connector group" can be active.  At the moment I have no L/CO for the 3X and 9X lines.  Just need to the time to wire 'em up and install them.

In another bit of phone news, a friend recently sent me a box of three Western Electric 302 desk sets.  That was quite unexpected and nice surprise... thanks, Don!  I have cleaned them up, and the dials on two of them needed to be rehabbed so I sent them to the "dial hospital" and got them back and have everything put back together.  I am presently awaiting some new cloth line cords for two of them.  I'll find a place for them, and some lines to attach them to...

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Updated March 11, 2017