palmerjrusa
Member
The original reason here dates from someone eavesdropping on Newt Gingrich's phone conversations way back when.
R8600 Do all IC-R8600's have the same dead carrier frequencies?
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The original reason here dates from someone eavesdropping on Newt Gingrich's phone conversations way back when.
@palmerjrusa
The rules/regulations on using communication receiving devices to listen to any transmissions the device can receive might be different in the United States but here in the UK you're only really allowed (legally) to listen to certain broadcasts. There used to be a saying that it's ok to listen to anything as long as you don't act upon what you hear.
palmerjrusa
Member
The blocking certain parts of the spectrum here dates from the "Gingrich affair", his phone one that is, not his other ones. Someone eavesdropped on his phone conversations and leaked them to the public, hence, of course, the vital need to fix this national "emergency". Some of our geniuses in Congress wanted to ban the sale of receivers blocked for certain parts of the spectrum, someone pointed out the details of the proposed legislation would have banned TVs.
I think the situation here is the same, you can listen to anything you can hear but not act on that information. Some states have obscure "scanner laws" preventing individuals from listening to scanners while driving, though I think radio amateur license holders are exempt from those laws.
I think the situation here is the same, you can listen to anything you can hear but not act on that information. Some states have obscure "scanner laws" preventing individuals from listening to scanners while driving, though I think radio amateur license holders are exempt from those laws.
palmerjrusa
Member
I need to get out my old AOR 8600 MkII and compare its sensitivity to my Icom ic-r8600.
Token
Member
Unfortunately, the above is an example of information found on the internet, how that shapes peoples belief, while being patently not true. I have seen the same story repeated in various forums and chats, but they were just as wrong.
First, the ECPA was authored and presented by a member of the other party, not the same party as Newt. His recorded calls were not a consideration. There is a rather large timeline issue that makes that 100% a fact.
The Gingrich cell phone recordings were made in December of 1996. The ECPA (Electronics Communications Privacy Act), the regulation that blocked cell freqs on scanners, was made law 10 years before that, in 1986. This is why, for example, the Realistic Pro-2004 was cell blocked, and it ended production in 1988. At the time the Gingrich cell phone recordings were "accidentally" made, it was already illegal to make and sell a scanner capable of receiving cell transmissions in the 800 MHz range, illegal to monitor cell phone transmissions in that range of frequencies, and illegal to share any information from such monitoring.
The wording of the ECPA was always (at least from a very early draft) made such that specifically scanners were illegal to make and sell, while various other receivers, spectrum analyzers, service monitors, TV receivers, etc, were legal. Scanners were defined as a radio capable of automatically scanning more than X number frequencies, I think the value of X has changed a couple of times over the years. Even today the regulation does not prohibit production of a receiver capable of these freqs unless the receiver has memories (and presumably can scan those freqs).
There are some specific services, frequencies, and frequency ranges that are Federally prohibited from monitoring. That means it is actually illegal to listen to / monitor them. Of course, unless you make recordings can anyone prove you did so?
An example of frequencies it would be illegal to monitor in the US are the Part 74 licensed studio broadcast links in the 26 MHz area or any Part 94 transmission (18 USC s 2510 (16) (E)).
However, in the US most freqs are fair game to monitor, as long as you do not divulge the contents, use the information for your own gain, or use the information to further a crime.
And to the OP, my R8600 has the same 133.6 birdie, very weak, about 7 dB above the noise floor, but there.
T!
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I have two USA R8600's, one -02 and one -04. The -04 does have the 133.6 birdie, with squelch at 30%, external antenna input grounded, AM, , squelch opens between 133.596 and 133.604 (Filter 1; narrower with Filters 2 and 3). My -02 model does not have the birdie. All settings same between the two units.
ka3jjz
Wiki Admin Emeritus
Just for winks - do you have any other radios in the vicinity of the 8600? You might be picking up a mixing product from the local oscillator of one or more radios in the vicinity.
If you do have more radios in the vicinity of the 8600, lock the 8600 on the birdie - then turn off the other radios one at a time. It could be a mix of the local oscillator of more than one radio (rare but possible).
Another test you can do is to remove the antenna entirely; do you still see the birdie?
Such a crazy mix could easily explain why other US users haven't noticed this. Mike
If you do have more radios in the vicinity of the 8600, lock the 8600 on the birdie - then turn off the other radios one at a time. It could be a mix of the local oscillator of more than one radio (rare but possible).
Another test you can do is to remove the antenna entirely; do you still see the birdie?
Such a crazy mix could easily explain why other US users haven't noticed this. Mike
Hi Mike,
I believe the reason is perhaps in the design of the R8600. I noted I have one -02 (blocked) and one -04 (unblocked). The -02 does not experience the birdie, hence matching the observations of other US based users. The -04 is equivalent to the EU model, and matches the observation of what AOR-262 has experienced - the birdie at 133.600 MHz.
When I observed, all other radio equipment were powered off. Only an Astron linear power supply and the 8600 under test were powered. I also had an LED lamp on as well as the PC (turning both off have no effect). The radios in my shack (via their respective Astron linear power supplies) have dedicated circuits to the circuit breaker panel. The PC and lighting are on a separate circuit. The two 8600's are ~1 foot apart horizontally; both share the same ground plane (copper sheet on the desk top, connected to my earth ground single-point connection) and each are connected via their ground connection to the ground plane.
Regarding the VHF/UHF antenna connections I have Alpha-Delta Delta 2 Coax switches with the common feed to the 8600 and one input to my feed-through panel (and from there to a PolyPhase lightening protector and onward to my antenna). The Delta 2 housing is connected to the same ground plane; when the Delta 2 switch is in the Common position, it grounds the antenna feed to the 8600's.
Dave
@escortz28 - Thanks for your reply and information. Much appreciated.
Token
Member
My -02 version does have the 133.600 MHz birdie, although it is weak, maybe 6 or 7 dB above the noise floor.
Designing such a wideband receiver with absolutely no birdies across its entire operating bandwidth would be a daunting task. As it is, the R8600 seems very free of birdies, but that does not mean there are absolutely none. I do note numerous birdies at the outer edges of the waterfall display as you tune, but generally they disappear before you get to that center freq.
T!
prcguy
Member
The R8600 and other radios like the Icom 7300, Elecraft KX3, etc, are direct conversion within the HF bands and their internal local oscillator is operating at receive frequency. When I have my 7300 or KX3 running and set them to the same operating frequency, the LO leakage can be heard. The same could be true for a pair of R8600s sitting next to each other and on the same frequency, the radios use down conversion on VHF but somewhere inside the radio its direct conversion HF side is putting out a birdie that might be picked up by another 8600 nearby.
Thanks for the explanation, appreciate you sharing your insight. When I tested for the birdie, I only had one 8600 powered on at a time. I did not observe any difference when I had both powered on.
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If this thread is still open, my 8600 picks up carriers every 2 MHz from 120 thru 136 inclusive. Only with antenna, so not internal. Bigger issue is spurious signals that do not break squelch but are strong enough to light up the receive lamp and stop the scan. Particularly bothersome if you have a 1 or 2 second scan delay programmed.
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