On our Iwatsu Omega IV EX-824 system has an issue. We had an electrical "brownout" a couple days ago so we had power loss on the cabinet, which turns the "Night Light" off on the DSS console. So when power restored we had to go lift the handset on the first station (no. 20) and press the "Night" button on the DSS so that all stations can hear the incoming calls. However, this time both the DSS and Station 20 had no power (DSS: no indicator lights or LED readout on display, Station: no dial tone/connection). So I discovered that I had 9 blown fuses (250v, 3/10a) on the 6 SUBK-M station cards and 1 fuse blown on the DSBF-M card in the cabinet. After replacing, I (perhaps foolishly) "reset" the CPU. Now I have power to the DSS, which shows the LED display info. and an indicator lamp for a station (on the DSS for off hook, I think) however, none of the phones are getting dial tone.

I had a technician (unfamiliar with this unit) notice that the red indicator lights were not lit on the SUBK-M station cards (or any other card on the top half of the cabinet so I'm guessing that something else was damaged. Of note, the Power Supply and the CPU both show power with indicator lights on. I would think if the backplane has power on the bottom (as indicated by the power supply and CPU lights) that it would have power on the top half.

So I'm thinking either EVERY card on top was blown or the backplane (top half) or the power supply or CPU are damaged. Any thoughts on how to test or use trial and error?

Thanks.

Somewhere on one of your cards some component has had all of its smoke released. You're trying to resuscitate what is probably at least 40 years old. That's outside even Iwatsu's Mean Time Between Failures stat and why your tech is unfamiliar with this system. I may be the only guy in Western NY that's even seen one of these babies and isn't afraid to admit it.

Trial and error is going to be about the only way you can resolve this, but by the time you've rounded up enough spares to start testing, you'll have probably wasted enough time to make just getting a new system more worth your while.

As I recall, system tones. like DT and ring back all come from a module on the processor card, so all your power troubles have probably damaged something on the processor. If the CPU card isn't working properly, nothing else will.

Also, the power supply puts out more than one DC voltage, (5 and 24 VDC IIRC)so that may be part of your problem as well.

If you can locate another CPU and power supply, that would be the place to start. Worry about programming when you have all your extensions working...

Is this system also known as the ZT-D? When i worked at an Iwatsu shop I think there was just one ZT-D left near me, and it's in the town next to where I live. Maybe one more in NYC that may have been replaced by now. I'm thinking the phones were 2 pair?

Or maybe the Omega IV is a different one - I'm picturing a brown and tan cabinet cover. I know it was somewhat common for those to blow a 3/10a fuse on the station cards. Hopefully the customer has realized it doesn't make much sense to try to repair that system. As mentioned above, it would be very unlikely for any tech today to be familiar with it,

Nope- This system is the system BEFORE the ZTD.. Cabinet was squarish- not long and tall like the ZTD. Programming was accomplished by watching LEDs on the attendant phone (Utility Series switch), or if you had the "Hi Feature" version, via the LCD screen on the attendant phone.

I still have 2 of these that I service, both customers are lawyers who are within a year of retiring and not needing or wanting an upgrade. Nice little systems.

Those Omega IV systems were some durable platforms. Installed many back in the 80s.

Ok it's the other one I was thinking of. I know of one still in service. Now a small shop with a couple guys and one of their dogs. That's the one I was thinking (I believe) I've replaced a line card fuse a few times. Back in my former office I used an 824 cabinet (it was square, unlike the ZTD cover) to put a portable heater on.

The system is probably still in use. Yes there's still many old Iwatsu systems out there, good durable systems.

Did you ever have the. er, um, pleasure of servicing an Omega III? The smaller switches had a 'Program Setting Box' that you connected to the switch, then flipped a rocker switch to enter programming mode. The larger switches had circuit cards with rows and rows of DIP switches for system settings and individual extension feature programming. You had to take the switch down, remove the card, make changes and re-insert the card and hope it booted back up.That was back in the days that a service call could be a couple of hours to do simple stuff. Fun times. That was even a pleasure after the EX 128s. Those were drink-inducing switches...

Ah the days of SPRG boxes and cross point cards. Don't miss those at all. IDS 128 flashbacks too.

Yes I did and holy smokes - I didn't realize that's how you'd program the Omega IIIs ! Thankfully I did just station troubles and moves. One had a a dial intercom, the other was by selecting the DSS key. I recall the 'motorboat' noise that was sometimes heard.

While I was with the company we replaced the smaller one, (8-16?) with an Iwatsu Adix, Pretty much duplicated the phones with 24 button Gen 2 phones (had to use a Gen 3 at the furthest point across the street). The guy wanted the Adix mounted up high like the Omega III, I had to secure plywood on the wall via an 8' ladder. If I recall correctly, we had to use he white-orange pair of each jack for the Gen 2 phones,

I heard the other Omega III that had the dial intercom and larger was also replaced with an Adix. I still carried 500 type network carbon transmitters when they were around.

Were the EX-128 or IDS-128s an Omega product?

IDS 128 was the big Iwatsu Omega system of the day.

I was referring to the IDS 128. Somebody else has an EX-128, but it was equally daunting to work on.

Those older systems, not just Iwatsu, by the way, used 3 pairs to get an extension to work. The white-orange pair carried the actual audio, the white-blue was called the bypass pair and the white-green carried DC voltage to light the lights. Then there were the programming boards with the most DIP switches ever seen in captivity.

I do not miss these switches.

"I do not miss these switches."

Makes two of us Brother.

I remember scrapping a lot of those cabinets!

Some customers that went from an Iwatsu Adix or ECS to hosted VoIP missed the TDM systems for various reasons. Mainly due to the inherent audio delay in hosted VoIP. Then there was the cost, many of the PBXs were bought and paid for years ago, They only called for moves/changes and the occasional service call.

It's mostly the over 40 crowd that has a tough time adapting to the changes. They're all used to Line Appearances and have a tough time wrapping their heads around PARK keys. And as you say, going from bought -and-paid for to monthly seat charges creates some sticker shock as well.

Don't even get me started with overhead paging. It''s easier, albeit waaaay expensive to do now, but was almost impossible to make happen when Hosted first came around

Yep I remember the early days of hosting. Customer had two phones on their desk in a lot of locations for paging and other features that they were used to.

I'd sometimes put a basic IP phone as with a DSS labeled PAGE. If we were fortunate, the phone would have a headset jack, and setting to allow it to auto-answer. The headset cable was connected to the page amp input. Worse case, I'd solder leads to the speaker terminals and have the phone in a page group.

Did the soldering many times on an Iwatsu systems using a Versa or the other similar one (MKT?). For an VoIP system, using a basic IP phone can be cheaper than an adapter of some sort.

I thought it was great how the Iwatsu systems had relay closures for whatever. We configured the keys on the phones for door openers, and other applications. One to trigger an alarm in that Icon system - forgot the name, (Signals?)...it would send an email alert and call the local emergency dispatch center. We'd label them red, but that didn't always prevent false alarms. That includes by me when changing a faceplate.

We used to tell customers that an Iwatsu ADIX/ECS would do everything but make coffee. If that was a deal-breaker, we could program a relay button to start the coffee maker...