ISP Information:
A 3G standard that increases the throughput of data transmission of CDMA by using a wider 5MHz carrier than standard CDMA, which uses a 200KHz carrier. WCDMA allows for data transfer rates as high as 2Mbps.
ISP Glossary:
Wideband CDMA - It should be noted that in the waning days of SxS, the Bell System added electronic front and back ends to the switches to improve performance. I'm not sure if they went as far as converting an SxS exchange into "common control" run by the front end electronics, but there was some up front processing.The Manawa office in Council Bluffs, IA (Omaha, NE area, 712-366) usedwhat was called 'Directorized SxS'. This was an outboard conversionused on some Ma Bell (and maybe others) step offices to approachcommon control. This conversion was most likely done in the 1960's,and provided dial tone to the subscriber, and recorded the dialednumber, either in dial pulses or touch-tone tones. For interofficecalls it then drove the switch train, and for intra-office it providedthe signaling (MF, dial-pulse, possibly even revertive - I dunno) thatthe called office expected. This installation lasted until the mid1980's when the Manawa office was cut to a DMS-10. Panel Type and 1XB had no provision for dealing with SxS pulsing. When 1XB came around, presumably the easterners assumed that any place which would need them would be panel.Panel used the 'revertive' signaling method, possibly invented by RubeGoldberg which, to make it very simple, the called officeadvanced the contact and the calling office told the called officewhen to stop. This was emulated in the #1 crossbar, as it wasintended to be compatible with the panel system. (I also vaguelyremember that the 1ESS was able to speak revertive as well.)When placing a call from a panel office, the revertive pulse soundscould often be heard as a distinctive 'scratch-scratch' sound duringdialing.I'm familiar with the way both the Omaha and NYC phone systems wereback in the electromechanical days, and both used panel and 1XBextensively with lots of revertive pulsing between the variousoffices. (Ma Bell's first full-scale panel office was in the Atlanticoffice in Omaha. Years ago I provided information about this to theDigest here.) Both areas used 5XB for newer installations until theearly 1970's.There were pockets of SxS around both Omaha and NYC, often appearingas DID implementations, but occasionally for POTS, as in the Manawaoffice I mentioned above. (I remember specifically that Columbia U inManhattan and Union Pacific in Omaha used such a scheme.) Many of theCDO's in the hinterlands surrounding Omaha (but in the dialing area)used direct-control step well into the 70's. IIRC, the panel and 1XBoffices (and some others) reached the direct-control step offices byway of a tandem office that provided the expected pulse signaling todrive the switch train. It was only when 5XB came out that there was an alternative to step in large step cities.I do remember that some 1XB offices were retrofitted to receive (andpresumably transmit) MF for interoffice signaling. (The O Streetoffice in Omaha was an example.) I assume that if they could speakMF, that there were provisions for dial pulse signaling as well. Interestingly I have found historical references to a Panel system being installed and utilized in the Providence, RI CO on Washington & Greene.I was always fascinated with the dialing arrangements in some parts ofRhode Island I visited during my younger days. IIRC, the Coventryarea was direct-control SxS (early 70's) and had a few varied accesscodes to dial nearby areas. (Dusting off very rusty memory cells ...)I also vaguely remember that the Scituate area had at least one officewith the 'directorized' step, and offered 7-digit 'sane' dialing intothe Providence area. I think there was also some SxS gear because my grandparents phones had the standard SxS dialtone and when called had the SxS ring and busy signals, though those may have been Panel signaling I'm not familiar with.It seems like many of Ma Bell's step offices used a similar type oftone plant, one with the 'flatulent' ringback, and that most of theirpanel offices (as well as most 1XB and many 5XB) used the veryfamiliar 'metropolitan' tone plant, but I know
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