Good idea, not in uls and unmarked cabinet, landlord won't fork over their
contact info, i'll keep pushing!

On Fri, Aug 8, 2025 at 12:17 PM Ken Hohhof <[email protected]> wrote:

> Any chance it’s a PIM issue?  I think we all dismiss PIM as something
> vendors talk about and other people (not us) have to worry about, but I
> guess it’s a possibility?
>
>
>
> Could be from your own equipment, or others on the same tower, like the
> FBI you mention.  If you can get contact information for them, maybe they
> could shut their transmitters off for an hour to see if your problem goes
> away?  If they’re not in ULS, is there a phone number on their cabinet or
> shelter at the site?  We tend to be intimidated by the three letter agency
> guys, but the few times I’ve had business related interactions with the
> FBI, they’ve been fine to deal with, even if they do dress exactly like
> you’d expect from TV.
>
>
>
> At least if you know it’s a PIM problem, that might give you some ideas
> how to fix it.
>
>
>
> Maybe the 7 GHz with something sub GHz is creating intermod products in
> lower 6 GHz?  If not on your exact frequency, maybe close enough to
> overload your receiver.
>
>
>
> *From:* AF <[email protected]> *On Behalf Of *TJ Trout
> *Sent:* Friday, August 8, 2025 1:46 PM
> *To:* AnimalFarm Microwave Users Group <[email protected]>
> *Subject:* Re: [AFMUG] 6ghz (lower) interference
>
>
>
> Thanks Tim!
>
>
>
> I hadn't considered that low level interferer to be a concern, I went
> ahead and temporarily reduced my channel size to move out of that space but
> haven't seen any improvement.
>
>
>
> Pretty convinced it's an external interferer but it's either not within
> the radios diplexers or it's some type of carrier scheme that the radio
> cannot detect (Tarana?)
>
>
>
> Anything with AFC shouldn't be an issue but who knows, I think the only
> solution is migration to a new band...
>
>
>
> On Mon, Jul 28, 2025, 1:32 PM Tim Hardy <[email protected]> wrote:
>
> If that -85 dBm carrier is co-channel or within the occupied bandwidth, it
> could be problematic. Typical co-channel interfering level requirement is
> around -99 dBm. Anything higher than that could be causing some issues.
>
>
>
>
>
> On Jul 23, 2025, at 6:24 PM, TJ Trout <[email protected]> wrote:
>
>
>
> Yes it's clean, only a tiny -85 carrier (link is -38 RSL) but I am
> starting to think that maybe the interfering carrier is not being detected
> by the radios integrated spectrum analyzer... Might need to do a secondary
> scan with an external device.
>
>
>
> around the time the radio started having issues the FBI installed some
> type of equipment on the same site, not sure if it is related but it looks
> like two sector antennas for land mobile radio? And also a 7ghz cambium
> link. I haven't had any luck in locating these transmitters in FCC ULS.
>
>
>
> On Wed, Jul 23, 2025, 1:04 PM Josh Luthman <[email protected]>
> wrote:
>
> Did you do a spectrum scan?
>
>
>
> On Wed, Jul 23, 2025 at 3:55 PM TJ Trout <[email protected]> wrote:
>
> Also only one side receiver is showing errors but the modulation is
> affected in both TX directions. SNR and RSL remain unchanged since install!
>
>
>
> On Wed, Jul 23, 2025, 12:53 PM TJ Trout <[email protected]> wrote:
>
> So this 6ghz link is still acting up, connects at 4096 qam and demodulates
> to each lower order modulation step by step about every 1 second, once it
> reaches the lowest modulation it drops connection and immediately repeats
> the same behavior again. I've replaced both radios and performed spectrum
> analysis and found no interference. One side we replaced the DC power
> supply and the other side has many links but this is the only link
> misbehaving.
>
>
>
> Working with the mfg (aviat) but even they seem baffled at this point.
>
>
>
> Link was installed 5 years ago and performed flawless with no
> configuration changes since installation.
>
>
>
> Maybe the borg can help?
>
>
>
> On Wed, Jun 18, 2025, 10:15 AM Ken Hohhof <[email protected]> wrote:
>
> Unlikely, but something that occurs to me is that if I remember correctly,
> unlicensed 6 GHz CPE radios are allowed to transmit at +30dBm EIRP while
> trying to contact the AFC, and then at +36dBm if given permission by the
> AFC.  So it’s not like they can’t transmit at all without OK from AFC, or
> are limited to very low power like indoor CPE.
>
>
>
> I think they first need to see the AP, which needs AFC permission, so a
> total screwup seems unlikely.
>
>
>
> *From:* AF <[email protected]> *On Behalf Of *Eric Nielsen
> *Sent:* Tuesday, June 17, 2025 7:33 AM
> *To:* AnimalFarm Microwave Users Group <[email protected]>
> *Subject:* Re: [AFMUG] 6ghz (lower) interference
>
>
>
> Send me a PM with the coordinates and/or callsign of the receiver that's
> getting the interference. I'll run the site and tell you if I see anything
> in the general area that could be suspect.
>
> If the link continues to receive interference, like others said, you
> should run a frequency scan to identify the interfering emission and its
> bandwidth. If the bandwidth is 40, 80, or 160 MHz, that's probably
> unlicensed.
>
>
>
> Lastly, if the problem persists, you should report it through the AFC
> interference portal: www.afcoperators.org
>
>
>
> On Mon, Jun 16, 2025 at 4:53 PM TJ Trout <[email protected]> wrote:
>
> One of our aviat lower 6ghz links started taking errors on one side, I
> haven't looked yet but I suspect it's interference from unlicensed ptp/ptmp
> gear, is this even worth chasing? It seems like I might be better off
> moving channels or bands?
>
>
>
> -TJ
>
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-- 
Thank you,

TJ Trout
Volt Broadband
209.480.3122 Cell
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