At 07:23 PM 03/14/07, Eric Lemmon WB6FLY wrote: >Nate, > >Several years ago, I chastised ARRL Labs for failing to report the basic >2-way radio performance parameters of 12dB SINAD sensitivity, voice >deviation limit, CTCSS deviation limit, and center frequency accuracy. I >did not get a satisfactory answer, but I suspect that there is a reluctance >to disparage the performance of name-brand Ham radios.
QST survives on the ads. The league doesn't want to risk the revenue. As the wise man said, he who has the gold makes the rules. >Nearly every Amateur 2m radio I have tested has CTCSS deviation far in >excess of the EIA/TIA recommended level of 750 Hz, and that level is not >adjustable in most radios. Pots cost more than fixed resistors and that would reduce the profits. >Alinco radios are the worst in this regard, >because the radios are made with fixed resistors that set the CTCSS >deviation level, which usually is two to three times the proper level. An >Alinco tech stated that the exact level wasn't important, only that it was >"high enough!" I own several Alinco radios that were delivered with CTCSS >deviation above 1500 Hz, and I modified them to bring their emissions within >industry standards. And such a mod breaks the warranty. It's sad but true that having a good sounding radio means having no warranty. >Such blatant disregard for industry-recommended >deviation levels is certainly not limited to any one manufacturer! How true. I've had to modify almost every oriental radio I've owned - from the Standard 806 (1972) on up. Every single one has been off-channel, over deviated, over-PL-deviated, spurious, or some combination of those flaws. In contrast, every commercial grade radio has been dead-on. Locally saying: ICOM = "InCredibly Over Modulated". A friend has a Kenwood TM-731A that was over deviated (6.9khz) and 4khz off frequency fresh out of the box. The TM-721A I had for a while was built so cheaply that I had to add an external alternator whine filter. The two Maxtracs that replaced it didn't need it. >My ICOM IC-207H mobile radio needed adjustment to bring the center frequency >and deviation within ICOM specs, but the model received rave reviews from >users who didn't realize how imprecisely the radios were tuned at the >factory. And too many repeaters try to fix the users radio problems with AFC'd receivers that chase the users off-frequency transmitters, variable-gain audio amplifiers that compensate for way-out-of-tolerance audio levels, etc. While I can see the point of having them, I feel that there should be a "straight through" option (maybe a DTMF command) that along with a DVR can show these users just how bad they really sound. >I realize that not every Ham has the test equipment to verify on-spec >performance of a new radio, but I would like to see much greater care taken >in fixing the critical performance parameters, before the radio goes out the >door. Costs too much in the manufacturing process - and won't happen unless Riley has an FCC tech van show up at some place like an AES or HRO warehouse and open up every box and check freq, voice dev and PL tone dev of every radio as it comes out of the United Package Smashers big brown truck. I'd be willing to bet that 90% of the radios won't meet the manufacturers own printed spec (much less the EIA spec) on voice deviation if you put your lips 2" from the mic grille and talk in a normal voice. And if you have the window of the car down a few inches at 60mph it's even worse as you unconsciously raise your voice to overcome the wind noise. And you can forget the PL dev spec.... >Moreover, I would like "Amateur-Grade" to mean simply that the radio >will operate on Amateur bands, not that it has been "dumbed-down" to >eliminate important performance adjustments in the name of reduced >selling price! The rules are there - the radio has to meet type acceptance to be sold here. That means that the manufacturer certifies that each and every radio meets spec when it leaves the plant. They lie. Slipshod and outright negligent manufacturing processes and procedures are letting radios that DO NOT meet spec get delivered to the distributors (like HRO or AES). They can't be expected to inspect and test every single radio. On the other tentacle, the local CB shops make a point of "peaking and tweaking" every radio they sell - they advertise it, and charge for it. Mike WA6ILQ
