The Robins AFB TypeIIA PMEL has experienced calibration problems the the new 33K procedure changes for the TS 4317 Radio Test Sets. When the power levels where increased the power termination boards will smoke. Areoflex engineers says that you should not apply CW wattage for no more than 15 seconds to get a power reading. This is barely enough time to get a stable reading RF amplifiers and RF Power Standards. Other bases have been sending Robins PMEL these Test Sets because of the frequency and wattage changes. We have more than 10 TS 4317's fail to operate over 100 watts during calibration.
Since the Watt meter part of this unit is not very reliable we recommend that the Wattmeters be limited for no calibration or calibration at frequencies below 400Mc and less than 90 watts of power. Most users have Bird watt meters and we recommend that users should use regular Bird watt meters (4391M or 43) when measuring CW power over 100 watts and frequencies above 400Mc. WE are not sure if the users are cooking the termination board or the change to the 33K caused the problem.
Another Note: Since most Radio shops and TS4317 users have stand alone DMMs and ocilloscopes we also recommend not calibrating these functions on the TS 4317's . This will help speed up calibration and not tie up half of the lab's standards calibrating these units.
Randall Francis
dear Randall, is necesary measure with the Peak Power Meter Gigatronics 8502A, because the time is very short of the transmission.
Green Hornet.
IMO limiting the unit especially for functions not cal'd is doing your customer a disservice. They may or may not have suitable substitute items they can use but the premise behind the 4317 was they could do everything with one item. Is our job to serve the customer or make our task easier? I personally haven't seen the new procedure, but I can't imagine there being a problem that can't be corrected without blowing up 10 units. Is somebody checking the wattmeter at low power first ot screen it to see if the users are blowing them up or if it a procedure problem?
Quote from: green hornet on 10-13-2012 -- 14:45:54
dear Randall, is necesary measure with the Peak Power Meter Gigatronics 8502A, because the time is very short of the transmission.
Green Hornet.
Not really sure what the green hornet is trying to say here?!
If they are TS4317s that are married to J Boxes for testing radios, then you are doing the customer a HUGE disservice by limiting the GRMs. Not sure how the Air Force handles the TS4317 vs the AN/GRMs or whatever other fancy names Aeroflex has come up with for them.
The whole point of them though is a one item test set for radios. Having to use an external scope, multimeter, or whatever really defeats their whole purpose, and saves you what, 2 hours of cal time? Now compare that to a radio shop that runs dozens of radios a day/week (not sure of AF workloads vs Army) who now has to stop and run a supposedly automated test by hand, because the PMEL lab wanted to save a few hours. Could end up costing the customer hundreds of hours a year......
I have tested piles of TS4317s and AN/GRM whatevers, all over the world, in the past and never had a problem with the wattmeter, other than maybe the occasional adjustment, but then again, I cannot recall testing them over 100 watts (maybe the Army vs AF differences?? I will compare the TO to the TB Monday, if I have a chance).
Just my take on them, like it or leave it.
Another thought, sorry for the edit, but AF PMELs have that much power to just arbitrarily limit or not calibrate major functions of a major end item/ pacing item? I mean the Army CAN limit stuff, with customer approval of course, but even then, 9 out of 10 times the customer will not accept the limited calibration if the item is used for that function, which = NRTS. Maybe I am working for the wrong branch, I want some power..... and not 200 watts LOL!
Quote from: PMEL Whore on 10-13-2012 -- 16:21:36
Quote from: green hornet on 10-13-2012 -- 14:45:54
dear Randall, is necesary measure with the Peak Power Meter Gigatronics 8502A, because the time is very short of the transmission.
Green Hornet.
Not really sure what the green hornet is trying to say here?!
Maybe peak power sensor go boom? +20 dbm max last time I checked......
Sorry, just realized this thread is from 2005. Thanks Green hornet...... -1