I don't know how, but I've been hearing California Highway Patrol on 42.6000, PL 131.8 and 146.2.
Picking up CA Highway Patrol in NY
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Skip / Tropospheric Ducting Forum
Discussion of Skip and Tropospheric Ducting Monitoring
tvengr
Well Known Member
When Baltimore County Police and MD State Police were using low band, they were frequently covered by the Los Angeles County Sheriff's Department.
Totally normal for peak sunspot cycle years for the MUF to be well up into the Low band frequencies. Not as much to hear as it used to be since not a lot of systems remain on Low Band. This "F skip" is likely to be present often this year and possibly next. vs the seasonal "Sporadic E skip" that tends to be seasonal and "sporadic" as the name implies.
LAPD used to be on 39MHz. I imagine they are gone now.
I've heard Missouri SP chasing tornados in years past.
Must be this
I had forgotten about these freqs and not listened to this range in years..I should scan again when bands open up. !
| 42.600 | WNUH519 | B | 131.8 PL | TRQ GAT B | Turquoise - Base - Solano (22) | FM | Law Dispatch |
| 42.600 | KUU356 | B | 146.2 PL | TRQ CEN B | Turquoise - Base - Buttonwillow (117) / Fort Tejon (102) | FM | Law Dispatch |
I had forgotten about these freqs and not listened to this range in years..I should scan again when bands open up. !
Thanks for all the replies. I can see why folks get into this!
I also picked up N. Sacramento and West LA on 44.620. Checking a couple others today.
Yeah, those are the ones, I figured it out last night.
I also picked up N. Sacramento and West LA on 44.620. Checking a couple others today.
After reading a bit about it, am I correct to assume that tropospheric ducting propagation usually doesn't go as far as propagation from E and F skips since the former is more dependent on local and regional weather conditions?
Tropo ducting is from a temperature inversion in the lower atmosphere so it is basically extending the ground wave coverage but it can be over distances up to several hundred miles. Ionospheric E and F "skip" from ionization of layers in the upper atmosphere causes sky wave signals to be reflected back to earth hundreds to thousands of miles away but skipping (hence the term "skip") the areas in between.
The F layer is the highest and is ionized to varying degrees varying with the season and the sunspot cycle. We are currently in a solar cycle maximum. The F layer is responsible for the regular long distance coverage of the "Short Wave" bands below 30 MHz with the MUF (Maximum Useable Frequency) varying with the ionization level and extending up to 50MHz or higher during solar maxima.
The E layer is lower and is subject to sporadic and localized ionization somewhat seasonal in nature. Since it is lower altitude, the reflection distance is generally less than F. It primarily effects Low Band 30-50Mhz but it can extend up to the FM band (100Mhz) and higher, sometimes even 150MHz. As the term Sporadic E implies, it is usually of brief duration and unstable. There is also the lower D layer that absorbs lower frequencies during the day but disappears at night and so extends AM Broadcast night time coverage.
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