dmine45

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Everything posted by dmine45

  1. How are you even able to call out from OSPSes these days? A couple of years ago AT&T got rid of their calling cards, so I haven't been able to explore OSPS systems like I used to. Unless you still managed to keep a working card somehow? And are you using the CVS technique to get to them or something else?
  2. I go all over the US for work and vacation, and when I do I like to see how the local network homes on various tandems (AT&T, MCI, Sprint) when I can. I like to do it from landlines and cellphones since both route differently. I also do this with VOIP carriers since often times they dump you on the POTS network at various places, and this can either be static or dynamic. (Can you say Tandem round robin?) Often times calls from landline, cellular or VOIP go to the newer "edge switches" that are in the format of NPA-xL (like 412-9L). I believe most of these are 5ESS based. But most of the time you can reach a 4ESS in the format of xxx-T. Anyhow, I was in a very rural place in Wyoming in May while on vacation. It was a rest stop in the middle of nowhere. The rest stop used to have a pay phone (you can tell it was there and removed), but they did have a microcell for Verizon Wireless (obviously fed by DSL). Doing my test for AT&T, it did the round robin as I suspected (some sort of VOIP backhaul) and I came up on 088-T a few times. That *used* to be the AT&T tandem for San Diego. They retired the 4ESS a few years ago, but now it comes up in the "new" voice that AT&T is using for the new generation "N4E" system.The N4E uses the old 4ESS software hosted in a virtual environment in newer hardware (lot smaller footprint and more in tune with modern packet switching). Sure enough, I was in San Diego last week and tried it from a COCOT. Yup, they do have a new N4E and has the new voice on the trailer. So I'm wondering how many of the existing 4ESS systems will be replaced by N4E systems? I also wonder how many 4ESS and N4E systems are out there. I found a N4E in Scottsdale, AZ (NPA 480) not too long ago. Haven't explored what else is new out there recently.
  3. I've seen a few, still as of May 2017. Saw one in former Commonwealth Tel. territory (now Frontier) in northeastern Pennsylvania (NPA 570). Sadly only a few of the phones still around are working, and those who are working are only sort of working (static, muffled sound, etc.). In other words, not maintained by the local techs - just left to pretty much rot in place. Full CO controlled, not a COCOT in any way. Up until about 2013 was still able to do intra-LATA long distance, but I think Verizon finally killed that off. Here's a pic of two from my last trip up to NE PA.
  4. From what I heard several years ago, the later 4ESS switches that were installed in the mid to late 90s were of a newer generation than those from 1976 to the late 80s. And yes, some of these switches are 40 years old!! But as TP said, over time I bet most of the guts have been replaced (though I do wonder about the announcement machines - some of which are quite broken!). But I think to say relevant, AT&T like a lot of other telcos are going VoIP. I know Verizon basically runs it's old school POTS TDM network and a VoIP network in parallel with gateways to cross connect the two worlds as necessary. Yeah, AT&T has introduced DMS-250, 5ESS, etc. into the long distance network, but the venerable 4ESS is still the backbone. Just curious what their strategy is to play in a mixed TDM and IP environment moving forward.
  5. That's a cool find. Thanks for sharing. I'll have to explore these soon.
  6. Mind if I ask who this provider is and if they're willing to sell service like that? Or did they do you a favor and provide you with a special sevice? I'm on a landline VOIP provider and wish I could do 101-xxxx FGD testing. Only place that I can do a limited amount of that is at work on an old fashioned DMS-100 Centrex.
  7. Interesting. That's one of the tandems in Houston, TX. Mind if I ask you what you dialed to reach it?
  8. Jman - Glad you went. I took the opportunity in 2005 when my brother who lives in Tacoma got remarried. Of course nobody but me wanted to visit. So glad I went - and I want to go back! Next time I'm in the PNW I'll make it an effort to go!
  9. As I recall, the AT&T 4ESS tandems where that recording resides are regionally based. 074-T is Philadelphia and serves the mid-Atlantic region. I live in that area and I home on that as well.
  10. Gonna say, Evan Doorbell did a segment on Cognitronics and numbers stations, and those were well before 1987. Back in the 80s I listened to a lot of shortwave and they were around in the early 80s when I was first scanning the bands
  11. I wish I had obtained recordings as well. I didn't know which was going to be the last one. I thought it could have been one of the Savannah, GA switches. I sort of lost interest in all of this when a good friend of mine passed away back in 2014 (TP knows who I'm talking about) who absolutely tracked every last 1AESS until he died. I mean tracked everything about them. You may still find his old posts on the Internet. Then in the summer of 2016 I asked a contact that he knew about the status of the 1As. He told me only a handful were left. So I started to keep track again. But as time went on, I sort of got bored again. I shouldn't have dropped my guard. But as others have said, an era is over. No more steps, crossbars or "electronically controlled analog switches" anymore.
  12. For me it's 005-T (Washington, DC 4ESS). So I assume it's not necessarily your local tandem, but the regional tandem that has that has that recording. (Sort of what they do with 800 numbers that are no longer in service) Also tried it on MagicCrap and I got 010-T (Baltimore, MD)
  13. I need to visit there again as well. Glad you were able to make recordings of the switch sounds.
  14. So I take it that Odessa was the last 1AESS office? So what was the date that it went down? June 1st? Another notch in the change of technology. The last crossbar offices went away in the US circa 1993, the last step or XY office in the US was around 1999, Canada was 2001 (Nates, Quebec). And it looks like the last 1AESS was Odessa, TX in May or June 2017. RIP old switching systems.
  15. If I have time before I leave on yet another business trip, I'll contact a friend of mine at iConetiv (the successor to Bellcore, Telcordia, etc. etc.) to see what 1As are still around. Sad when Lafayette Main goes away since that's where my friend Mark Cuccia lived. He was the one who always tracked the last 1AESS switches in the US. Sadly he passed away in 2014. That's why I'm keeping this thread alive in his memory. (TP knows who he is too.)
  16. http://localcallingguide.com is another great resource.
  17. Yup, they're dropping like flies. Now that it's April, I bet there are less than 5 left. Wonder how we can test the remaining ones?
  18. Is that number consistent with all 1AESSes?
  19. TV Stereo used a different pilot for the L-R signal. Otherwise it was almost identical to FM Stereo. Yup, the 800 MHz band we know and love for cellular (the infamous "A" and "B" bands) were the old UHF channels 70 to 83. With the advent of ATSC (now known retroactively as ATSC 1.0), channels 52 to 69 were removed in 2009 and those are now known as the 700 MHz LTE band. With the upcoming ATSC 3.0 that's around the corner, UHF channels above 37 will be removed. That will become more bandwidth, probably for 5G wireless. In addition, TV stations are volunteering turning in their licenses, which will free up even more spectrum. With ATSC 3.0, the 6 MHz channels will handle up to 4K video and you can compress the living snot out of 1080, 720 and 480 (tons of sub-channels). So the now pretty much empty UHF band will shrink once again and will be littered with wireless. Yup, CED killed RCA. Sadly. Had they foreseen that lasers would come into play, they could have taken the market away from Sony and Philips. But that's another topic! As for upper cable bands - many people didn't realize that they co-existed with existing OTA stuff. Cable channels 14-22 were the infamous Air/Police band (and ITMS mobile phones back in the day!), and upper cable channels were mapped to UHF channels. Back in the 80s, I had an upconverter that converted cable channels 14-36 to upper UHF. Wonder if it can be repurposed in this day and age?
  20. I know on the DMS-100 Centrex where I work, you use the vertical service code before dialing 9 for outside line. So it's *67 (or 1167) + 9 + number. Otherwise as TP said it could have been misinterpreted as dialing 911. (Which is why they recently changed it for us to 9+911)
  21. What's the best way to check to see if a 1AESS office has been cut over to a new switch? If I recall, there were certain test numbers you could call on a 1AESS that only existed on that platform that disappeared when it was cut over to a new packet switch. I believe that it's now early April that all of the 1AESS switches are now gone. However, I do want to check to see if there are any left.
  22. Carriers couldn't wait to get rid of AMPS. It was a spectrum hog. They could compress a lot more GSM and CDMA calls in the same channel space. In fact, AT&T finally got rid of 2G (TDMA) in January 2017. Again, lack of market share, spectrum hog, and everyone had finally moved on to GSM or LTE. In fact, 5G (actually not really a consumer standard) is on its way soon. More signals, less need for the older crap. It was pretty amazing. In 2008 AMPS went away, in 2009 NTSC (analog) television went away. And in a few years, the current digital ATSC will go away (ATSC 1.0) because ATSC 3.0 is around the corner. And that will use even less spectrum because the FCC is giving that away to the cell companies. ATSC 3.0 uses more compression than the current ATSC 1.0 does. And don't get me started on the landline side of things. I see huge changes in the next 5 to 10 years. Ain't technology grand?
  23. I've been working with Evan Doorbell to release some more of his raw (unnarrated) tapes. He has released 8 tapes so far. They are from New York City and Long Island, NY. I'm posting them here: http://www.evan-doorbell.com I hope to get more from him soon. Enjoy! EDIT: I've updated the URL since I moved it to a new server.
  24. I'd like to hear those tapes as well. Really loved that series! One of the masterminds behind that contacted me via the website a few months ago.
  25. Not sure what they use as their platform, but it's not the traditional OSPS that we've been used to with the post paid platform.