PassPort exposes dirty secret
One thing about PassPort trunking protocol: It exposes — and overcomes — the dirty little secret among “good” dealers, “bad” dealers and their customers involving LTR systems.
LTR is a widely used analog trunking protocol that works with single sites. PassPort is a widely used digital trunking protocol that can be added to existing LTR systems to allow multiple sites to be networked.
PassPort uses subscriber-unit electronic serial numbers; LTR doesn’t. LTR’s deficiency allows customers to add LTR radios to their fleets without telling the airtime system operator — and the system operator may never know.
“I always jokingly said I could tell you how many LTR mobiles we were billing for, but not how many were on the system,” one dealer said, on condition that he not be identified.
For example, one customer had bought 20 LTR units from the dealer. But when the dealer converted the customer to PassPort, the customer registered 34 units. The customer’s explanation? “Oh, I guess we’ve been buying a few units, here and there.”
Some dealers with, let’s say, a “deficient conscience,” sell LTR subscriber units for use on someone else’s system, whispering to a similarly conscience-challenged customer: “You don’t have to tell Joe at Gullible Communications that you have these units. He’ll never know.”
Our dealer said, “If we ever charge an LTR customer for one more radio than they think they have, they call and raise Cain. But if we charge for fewer than they have because they bought some elsewhere, the customer thinks, ‘too bad’ — it’s our problem. That’s theft of telecommunications service, just like stealing cable TV or telephone service. We know it goes on, but it’s difficult to prove.”
Unscrupulous dealers happily sell radios to someone else’s airtime customer, helping the customer to avoid monthly subscriber unit airtime charges. In fact, the “bad” dealer can charge a little more for the radio because the stolen airtime more than offsets the “premium.”
“Stolen airtime is, and always was, a problem with LTR. LTR never was the best protocol; it was only the most common. PassPort is stopping all of that thievery,” the dealer said.
Two other dealers said that as they convert LTR to PassPort, all subscriber units have to be registered by electronic serial number. They expect an eventual revenue increase of 30% — all from billing for previously stolen airtime. It’s enough, one dealer said, to pay for the PassPort installation.
The dealers spoke about PassPort, but asked for anonymity. Much of what they said was complimentary, but to elicit words about any minor problems required secrecy.
“Everybody has software problems,” the first dealer said. “It’s been a nightmare. Also, we have been through numerous iterations of firmware from Trident and Kenwood. We’ve tried lots of different radio manufacturers, and all seem to have some hiccup.
“We’ve been in the trunking world for so long, when you connect A to B and C to D, and you tune it to manufacturer’s recommended specs, and when the RF works, there’s not much else a dealer can do other than to use normal good industry practices when building out the RF infrastructure as far as transmitters, receivers and combiners are concerned,” the first dealer said.
A second dealer disagreed, at least partially.
“Since our PassPort system began three years ago, Kenwood has been the single most successful product line that we’ve had. Every time we talk about radios that work, that don’t work or that have remaining problems — and they all do — the Kenwood radio has worked better than anything else that we’ve held in our hand and worked with,” the second dealer said.
He said that to help with its remaining problems, Kenwood had engaged a software company that had had some success with the PassPort protocol.
“But we are open and eager to embrace any manufacturer that puts out a subscriber unit that works as it should, and that includes Icom, Vertex Standard and Ritron. Our experience with Motorola has been minimal. Motorola has not shown a strong interest in working with us because we’re the ‘other half,’ a non-Motorola dealer. But I hear that their unit works well,” he said.
The PassPort system is a relatively complicated network, the second dealer said of the infrastructure. “It isn’t something you construct, bolt and play. You have to have smart people to configure your system and keep it operating. We have helped many dealers work out their problems, and it has been a pure lack of knowledge on their part. Something that took them weeks, we fixed in hours. PassPort is not for the faint of heart. You have to have savvy people.”
‘Home alone’ OK but not ideal
To operate PassPort requires at least one exclusive (non-shared) channel per site for the system’s “home” channel. A subscriber unit’s transition from one networked site to another works when it has to register on the next site’s home channel, but registration is faster when each site has a second exclusive channel called the “collect” channel.
“If you don’t have a collect channel and the home channel is busy, the unit can’t register until the home channel is free. A mobile could wait a long time before it registers and is available for use” without a collect channel, the first dealer said. “Having multiple exclusive channels would be ideal.”
Some dealers are awaiting licenses for exclusive channels obtained with successful bids in FCC Auction No. 40 last September. Our first dealer bought a number of channels; the second missed the auction and regrets it; and a third bought a large quantity of channels for “a surprisingly low price.”
‘Strongest signal’ selection
The second dealer said that it would be an advantage on his system to have a subscriber unit with the ability to select a site with the strongest signal when it de-registers from one site and re-registers with another.
“Strongest signal selection cuts the downtime of the radio as it toggles back and forth from an improper site selection. Yet, it takes more time to makes the registration. But it’s better to extend the selection time than to have to go through the selection process again and again,” he said.
The dealer said he had found that Icom’s PassPort subscriber unit with strongest signal selection works well. But with his brand preference well established, he said that he is pleased that Kenwood is about to add the strongest-signal feature to it subscriber units.
A system engineer offered the opinion that, with a network of towers with a lot of overlap, strongest-signal selection offers “a little more precise way to engage a site.”
“We are optimistic,” the second dealer said. “We always have been optimistic about PassPort. The current level of performance has been a long time coming. We hoped for a quicker resolution to some of the problems that plagued us for years, particularly in subscriber units.”
“We looked at all the network systems. Most were analog, without a digital migration path. PassPort and its accompanying repeater controller are digital, so they’ll work with possible future digital subscriber units and repeaters,” he said.
For the dealer, networking was a must, although PassPort allows him flexibility in keeping some customers on LTR and some PassPort users with single sites or a restricted list. The dealer added that he knew his company couldn’t survive in the two-way radio business with single-site systems.
Bishop is editorial director. His email address is [email protected].