How Low-Bid Specs Affect Radio Features Like PL, CTCSS, and DPL

[DonTom]

But these are busses built by the lowest bidder and likely lack that sort of feature.

I better explain here how low bid works, as I had to deal with such where I worked in C&C of SF.

Let's say it's a new radio system. First step is to have the correct department put the needed specs in writing, such as the department that deals with radio communications (my department). After all the wanted specs are in writing with many "MUST HAVE <whatever>" then it goes out for bid.

So the low bid and the high bid will have all the exact same wanted features.

But there is endless "cheating" in this method. I will give an example on older radios that are less technical here.

Must Have "Private Line" . Guess what? They may all have it, but call it by a different name. The clerks who put out this stuff for bid don't know that GE calls the exact same feature as "Channel Guard (CG)". So only Motorola has "Private Line(PL)". So only Motorola qualifies as "low bid" but are normally the most expensive and best stuff made. The CD /PL is just their name for "tone operated squelch". So that is how the low bid can be the best stuff made and we get it anyway.

No doubt they play the same game buying new EVs. However, if they have no experience with EVs then anything can happen, as they will not know what to ask for.

-Don- Auburn, CA

 

[John From Detroit]

Private line is generically called: Continuous Tone Controlled Squelch System.
I have radios here ranging from about $5.00 (Baofeng UV-5R from Ali Express or Temu 5-20 bucks) to about $2,000 new in 2006 (Kenwood TS-2000) all have that feature. Even m 1978 Wilson WE-800 has half of it. (Can generate 100 Hz tone used for CTSS locally)

However lowest bit is not always taken I can cite two cases
Remember the shuttle that blew up on takeoff due to a failed seal on the two-piece booster?
That was not the lowest bid. Lowest bit had no such seal and was a one-piece booster, but NASA took the higher bid due to a key senator on a budget commission representing where that company was located. Stupid design, joint was upside down.

Flint water mess. The company that got the bid sold what turned out to be the problem causing water to the city at 75% of what they used to pay Detroit Board of Water Commissioners. Who provided safe water. But the lowest bid.. Detroit Water offered to cut the price in half.

Again the decision was political and people wound up dead.... Or worse.

And that's why I don't like talking politics here. IT drives up my blood pressure.
This however is facts. And the politicians involved are out of business today.

 

[DonTom]

Private line is generically called: Continuous Tone Controlled Squelch System.

Yeah, of course I know the generic name is "CTCS". As long as the City Hall clerks don't know, then all is fine.

If they did know PL was just another name for CTCS, they would change it on the spot. Their job is to save money. Our job was to get the best stuff possible, regardless of cost.

Bottom line is "low bid" often works well when the game is played correctly.

-Don- Auburn, CA

 

[John From Detroit]

Yeah, of course I know the generic name is "CTCS". As long as the City Hall clerks don't know, then all is fine.

If they did know PL was just another name for CTCS, they would change it on the spot. Their job is to save money. Our job was to get the best stuff possible, regardless of cost.

Bottom line is "low bid" often works well when the game is played correctly.

-Don- Auburn, CA

Oh I agree and figured you knew PL - CTSS - assorted other names. Just like "Touch Tone" = Dual Tone Multi Frequency (you likely know that too)

Many here do not. But then you clearly have training (As do I but you have more) and Expierence.
I'm an Extra class ham. (Suspect you might be) sounds like you are a Radio tech. (many of them (most?) are hams as well)

 

[DonTom]

Oh I agree and figured you knew PL - CTSS - assorted other names. Just like "Touch Tone" = Dual Tone Multi Frequency (you likely know that too)

Many here do not. But then you clearly have training (As do I but you have more) and Expierence.
I'm an Extra class ham. (Suspect you might be) sounds like you are a Radio tech. (many of them (most?) are hams as well)

RCA calls it "Quiet Channel". And then there is DPL (Digital Private Line).

Yes, I was an Extra Class in my teens, when the so-called "Incentive Licensing" first started. when I had to do all the testing, including sending and receiving CW at 20 WPM.at the FCC office in San Francisco. I also have the Frist Class FCC License with Radar Endorsement from that time as well.

BTW, you can check the ham license class of anybody on QRZ.COM.

However, a story comes with my Extra. There was a two year wait required after having the Advanced Class which I just received. But it was four years for me. Because I was drafted two days before my two years was up! So then I had to learn CW all over again after being in the Vietnam Jungles for a year. But it didn't take long and as soon as I could send and receive all day at 25 WPM I went to the FCC office again and got my Extra. I took my own Curtis Keyer with me. Brown Bros. Paddle (still own). People there were impressed with my sending. I made no mistakes at 25 WPM and sounded just like their tape, expect their tape was at 20 WPM.

Shortly after that, it was reduced to a one year wait. And then later, no wait at all.

I passed every FCC test on the very first try. Never flunked one.

BTW, do you keep your callsign top secret or something? If not, what is it? Do you work any CW?

Now to get back on subject. I am now back in Reno. It was 19°F. when I got here yesterday night in my Chevy Bolt. I recharged it outside on top of the snow. It charged right up normally, I noticed no difference in charge times compared to a nice warm day, but I assume it was a few minutes longer, just nothing noticeable.

But I assume it would have taken longer if it were not just driven for 100 miles--but even in the much colder weather at the 7K' Donner Summit.

73, -Don- Reno, NV AA6GA/7

 

[John From Detroit]

RCA calls it "Quiet Channel". And then there is DPL (Digital Private Line).

Yes, I was an Extra Class in my teens, when the so-called "Incentive Licensing" first started. when I had to do all the testing, including sending and receiving CW at 20 WPM.at the FCC office in San Francisco. I also have the Frist Class FCC License with Radar Endorsement from that time as well.

BTW, you can check the ham license class of anybody on QRZ.COM.

However, a story comes with my Extra. There was a two year wait required after having the Advanced Class which I just received. But it was four years for me. Because I was drafted two days before my two years was up! So then I had to learn CW all over again after being in the Vietnam Jungles for a year. But it didn't take long and as soon as I could send and receive all day at 25 WPM I went to the FCC office again and got my Extra. I took my own Curtis Keyer with me. Brown Bros. Paddle (still own). People there were impressed with my sending. I made no mistakes at 25 WPM and sounded just like their tape, expect their tape was at 20 WPM.

Shortly after that, it was reduced to a one year wait. And then later, no wait at all.

I passed every FFC test on the very first try. Never flunked one.

BTW, do you keep your callsign top secret or something? If not, what is it? Do you work any CW?

Now to get back on subject. I am now back in Reno. It was 19°F. when I got here yesterday night in my Chevy Bolt. I recharged it outside on top of the snow. It charged right up normally, I noticed no difference in charge times compared to a nice warm day, but I assume it was a few minutes longer, just nothing noticeable.

But I assume it would have taken longer if it were not just driven for 100 miles--but even in the much colder weather at the 7K' Donner Summit.

73, -Don- Reno, NV AA6GA/7

No I've posted my call several times. Even though I have an Extra ticket I still use my Tech call WA8YXM. So much stuff is engraved with it and it's been me for well almost 60 (5 years so I stick with it. Living as I do now in an apartment you can find me on D-star most of the time
XRF757A/XLX307a (Quadnet you can get there via YSF, DMR and more openquad.net for info
REF035C (net at 1500 UTC M-F) REF024C most of the time using an M1KE (Off from midnght to 4AM EASTERN) and my local repeater allstar 474420 echolink W8ACW-R I'm an admin on the system. Working on getting limited HF ablity again but It will likely be 40-6 Mobile and low power less Clay can fix my TS-2000 or I get a new one (My eyes do not do "smaller than a grain of rice" parts any more.