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Hey everyone, I'm hoping to get some help with a bit of a head-scratcher. I recently installed a Btech 50 watt radio with a Tram 1181 antenna on an MNO mount. I've double-checked that everything is grounded properly, and while the radio transmits just fine, the reception is absolutely plagued with noise. Here's the weird part: if I completely remove the antenna from the MNO mount (but leave the mount itself attached to the bracket), reception improves dramatically! It's still not perfect, but it's a world of difference compared to having the antenna screwed on normally. In its normal configuration, the reception quality is worse than my handheld radio, and the range is definitely suffering too. I'm at a loss here. Any ideas what could be causing this? I am thinking antenna but I am not sure. VID-20240417-WA0019.mp4

I want to describe a problem I am having with my GMRS communications, so maybe the experts on here could offer some ideas. Out of respect for everyone’s time, I’ll first describe the issue, and my setup, so no time is wasted asking. I’ll also describe a number of steps I’ve already tried (nothing worked), again so no additional time and effort is wasted suggesting something already tried. Problem Description: Mystery Static Bursts during RX/TX During Standby: No problem, no static detected, squelch not broken. During RX: Occasionally I will receive a burst of static while someone else is modulating. It seems to happen at random, maybe about once per minute and last for 3-5 seconds. It is not enough to completely obliterate the receiving transmission, but enough to seriously degrade it. It sometimes will also happen during receipt of repeater Morse code identification, but not every time. Time of day does not seem to matter, morning, afternoon, evening, as this happens most times someone else is modulating. So far, this only seems to happen on 462.650/467.650. It is difficult for me to experience or verify this problem on other channels/frequencies due to little or no traffic on them in my area. During TX: Others have reported that while I am transmitting, occasionally they will hear a static burst on their end, similar to what I hear during RX, and sometime this static is strong enough to completely knock out my transmission. It seems to happen at random, and again last for 3-5 seconds. During long transmissions, the other person will hear me ok at first, then I may drop off completely mid-transmission, and then resume. My Radio Setup: Setting: Single family style residential brick home in typical subdivision Primary base-station radio: AnyTone AT-588 – Power output setting: Middle (25w), WB setting: 20KAlternate radio: Midland MXT115 – Power output setting: High (15w)Antenna: Tram 1486 (trimmed for 462mHz), roof mount, approx. 20’ AGLCable: LMR400 (approximately 36’ length, PL-239 connectors)Power Supply: DuraComm (measured voltage 3.9v, constant)Excellent repeater reception/access (Dickenson Texas 650), with correct tones, LOS distance 15.5 miles Other Notes: Wall penetration for cable routing to attic/roof contain 4 cables: 1) Primary GMRS antenna (Tram, outside roof mount) 2) Alternate GRMS antenna (factory cut for GMRS, attic mount) 3) Scanner antenna (attic mount), and 4) CB radio antenna (attic mount).Cable grouping above possibly runs near electrical outlet wiring.Tested with all radios off except one being tested.Tested with primary radio on, scanner on. Radio experiences static bursts, scanner does notTested after swapping primary/alternate radios. Problem persists on new primary.Antenna cable routing is same for all radios and terminates in attic; except for the primary antenna cable continues higher to roof a penetration. All equipment is fairly new (within 3 months old)There are two laptop computers (one uses Bluetooth) and one printer nearby, but typically these are off during radio traffic.900 mHz wireless telephone base nearby, originally in immediate vicinity but moved 8 feet away from radio and antenna cables. Solutions I Have Already Tried: Replaced primary radio. I sent the AT-588 back, and they sent me a new one (verified by different serial nbr). Problem persisted. Replace alternate radio. I had a second MXT115 in my truck, so I swapped them. Problem persisted. Grounding antenna: Ground wire run from antenna base to attic mounted ground (distance to house earth ground impractical to reach). Conductive isolation of antenna from mast and removed ground. Normally per instructions, antenna is bolted to metal mast with supplied connectors. Thinking the mast may be holding static electricity, I insulated the antenna from the mast using pieces of rubber. The mast itself is bolted to wooden roof with composition shingles. Alternate Radio, but using same antenna/cable: See primary and alternate radios above. Scanner backup: Using a separate scanner tuned only to 462.650, the scanner does NOT pickup the static burst. Moved home Wi-Fi router and wired hub away from radio and antenna cables. Previously in same vicinity, move to about 8 feet away. Attempted to (temporarily) shield radio from WiFi signal using aluminum foil. Moved home wireless phone system away from radio and antenna cables. Reroute antenna cable in attic by unraveling/un-coiling excess to help eliminate possible bleed-over. Swap out power-strip feeding power supply/radios. Things I Have NOT Yet Tried: Moving primary/alternate radios some distance away from the power supply (due to time or practical matters). Currently power supply is right by radios. Complete shutdown of all electronics (including lights) in radio room. Replacing LMR400 cable (could be needless expense, since the one I am using seems good) Replacing antenna (same as above, could be needless expense) Recap and Summary: I am experiencing unidentified static bursts on frequency 462.650/467.650. Appears to be isolated to antenna/cable, or some type of nearby house electrical problem. I’ve been dealing with this for some time, and am running out of things to try. Thanks in advance to anyone who can offer suggestions. This is truly frustrating. ...