In my room all my test signals are contaminated by a soft peak at about 1.5 MHz. When I connect a simple, 1-meter long wire to a scope I see damped sine waves at this frequency with a decay period of a few cycles, recurring at random times. I suspect this is caused by our CIAT air conditionning system.
Does anybody has trouble with this brand of air condionners?
Jean-Pierre Coulon wrote: ===================
** I used to get RFI in test gear from the cordless phone in the apartment above me. On the 30MHz band, analogue FM.Got my revenge by listening in on my radio scanner. Heard a lotta s*it I was never meant to know about ......
...... Phil
I brought a small AM radio receiver. I hear sort a white noise in the audible domain, same in the 1.3 to 1.7 MHz domain. It seams to increase when I get closer to the air conditioner.
amdx snipped-for-privacy@knology.net wrote in news:sm3auc$56i$ snipped-for-privacy@dont-email.me:
Turn off everything in the house. Except the analyzer of course. Then if it is no longer present, one by one, turn on those items you previously de-energized until you spot it and hence the culprit. If it is still there after turning everything off, it is external to your abode and running gear. Could be a neighbor's microwave.
We got enormous damped ringing spikes from a VFD to a blower on the roof.
Seems like one could turn gadgets on and off to see which ones are the culprits.
The source could be non-local too.
One could wave a probe around and zero in on the source.
I ran into that in the '70s. Station WOAI. 1200 AM, San Antonio's news, traffic and weather station
On 11/5/2021 9:51 AM, snipped-for-privacy@highlandsniptechnology.com wrote: [snip]
Don't take all the fun out of it. ;-)
Got a bug in the AC?
I worked on a system some years ago for a group I can't name. Cell phones used to be analog voice with digital signalling, not encrypted in any way. Anyone with an analog receiver could listen in to phone calls. While testing the system I recall one conversation that went on for some time. I only listened to it periodically as required to verify voice quality and hang up detection, but it was easy to tell someone was being dumped and was extremely unhappy about it. I think the call lasted over an hour. Most cell calls at that time were no more than a minute, "Hi, don't forget the hamburg rolls and pick up some milk." I don't recall the price, but cell phones were far from free calls and charge 'em for the data! lol, there was no data to charge them for.
We actually had a cell base station to test with. That was pretty cool.
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