Does an SE interfere with an S7

[Michael B]

Bench testing these platforms together had the following results
Samples of the following were tested
RX65 S7
955 S7
Pro78SE
XTR-690SE

Placing a scope on the alarm line of from one of each platform and compared distance for worst case (horn to horn) and distance for standard mounting (dash or window).

To start I selected the RX65 with nothing else on.
After power up, the alarm line had a quick pulse or two and then was quiet.
I watched this unit all by itself for 20 minutes and observed the following.
Self cal at 1 minute and 45 seconds lasting for approx 10 seconds
Self cal at 5 minutes and lasting approx 10 seconds
Self cal at 8 minutes 30 seconds lasting approx 10 seconds
Self cal at 12 minutes and lasting approx 10 seconds
Self cal at 15 minutes 30 seconds lasting approx 10 seconds
Self cal at 19 minutes and lasting approx 10 seconds


I then plugged in a 78SE and made sure I was comparing any potential interference issues between the self cal periods so as not to confuse interference with a sel cal period that appears to be every 3 minutes and 30 seconds after the 2nd cal


When pointing horn to horn, the units had to be approx 12ft apart to not cause any pulses on the alarm line but when placed side by side with both horns facing the front windshield, the units had occasional interference at 12 inches away or less but did not appear to have interference when placed 24 inches away

I tried the second SE unit with similar results.
I tried the second S7 unit with similar results.

When having the RX65 in Ka International mode and turning on the SE while pointing horn to horn at less than 10 ft the RX65 alerted Ka band

When having the RX65 in Ka USA mode and turning on the SE while pointing horn to horn at less than 10 ft the RX65 alerted X band

Yes, I said X band.



Note added 6/16/11
One think to note, it you pressed the menu button on the SE, the unit will stop sweeping and cause the S7 to alert in the neighborhood of 35.45 even at the distances noted above because it stops sweeping.

The S7 also stops sweeping when enterning the menu mode and can cause a similar issue to the SE
The CW during the S7 menu mode is not always the same and as a result has caused the SE to report Ka as well as all the RSID frequencies.

[frankw]

Thanks for your hard work Michael B. That is some very interesting results.

[frankw]

Ive been running my 693 with my old 985. I havent really noticed any interference but my 985 is probally due a tune up.

[djrams80]

Not as bad as I thought. The X band thing is pretty funky.

[TRun]

Great stuff now how about whistler vs m3 and m4s?

[happya$$]

Thanks Mike for your hard work

[Michael B]

I will try to get an M4 tested against the SE tomorrow.

M3 will have to wait a bit

[Nvidia78]

Thanks for the hard work you put in Mike, In International mode it sweeps all of the KA band right? and USA mode it only sweeps what is used here in the USA? So the leakage is out of the USA band Seg?

[Michael B]

I recall the Ka USA only looks for the areas around 33.8, 34.7, and 35.5 while the Ka International looks for 33.4 thru 36.0

I have no idea why the unit would report X band when in the Ka USA mode and Ka band when in the Ka International mode when powering up an SE.

I should say, I understand the Ka response as it is caused by a harmonic of the 1st LO from the SE but there is no X band component from the SE that should cause the RX65 in the Ka USA mode to alert X band yet it did.

Go figure.

[Jag42]

Nice thanks for the test. I have a old Whistler and i can get Ka and K falses on the V1 all at the same time by plugging in the unit on/off