January VHF 2023 – Rebuilds, Power, Transmission Line

Just as I finally constructed something for comfortable, long-term operating in the Patriot, I sold it. I’ve stated a few times that January 2023 requires an almost full rebuild, but with the **correct** roof rack on the way so I can continue to use the old system, the operating desk may be the only piece that’s left, but I do have some questions for myself I’m working to address.  

Let’s have a brainstorming session: 

Power may prove to be a problem, but that’s something that I’ll have to putter around with a little bit. I have an AC inverter battery pack that can be charged via solar. The inverter within the battery and panels seemed to produce a bit of RF Noise around 50mhz, and when they were run together it rendered the band virtually unusable. I may attempt to isolate these in some way so I can continue to use it for Laptop and Rotor power, however while running /P in June I discovered that my car offers a “Utility Mode” during which all 12v systems (including those run from the lighter plug) are powered through the High-Voltage Battery. What I need to do is look a little further into the way that this function works, does it shift where the power isactually coming from, or does it just continue to trickle charge the 12v battery when the motor isn’t running? 

When installing my day-to-day radios in the Kona, I decided to use the seat bolt Lido Mounts – these are great, however they do not offer me the same range of motion with the passenger seat. Part of the way the desk secured was by moving the seat forward to the point where the desk wedged in the dash to reduce movement. I’m thinking in this design an additional board going across the legs, and then securing that board using ratchet straps on bungee cords to the seat rails. 

Desktop will likely be about 2.5’x4’ with room for control heads and a laptop – likely, as with the previous system, RF Decks will be below the desk with coax running in through either window on the passenger side, allowing for the shortest runs possible. RG-213 has been my coax of choice up through now due to finding a spool for $20 at a hamfest, and while it’s performed well enough, I would like to upgrade it on bands above 2m. Unfortunately, I don’t foresee making too many adjustments to that before getting on the air this time around though.  

Using the 213, I have losses of roughly:  

4% @ 50mhz, 6% @ 144mhz, 8% @ 222mhz, 11% @ 432mhz, 17% @ 902mhz, 21% @ 1.3ghz 

2.4ghz the coax run is so short (only about 1ft), my loss is about 3%, but that’s essentially the maximum rated frequency of that cable. 

Above that however I have small patches of LMR-240, and Ultraflex that I can repurpose and shuffle around to make work for these cases as we’re only looking at two additional bands (3.4 and 10ghz), and if there’s some extra I’ll likely move that down the 2.4 as well. 

Now… if we can just hold out and get a few nice days next week when the rack is in, and for me to get the garage opened up to get some work done, or at least cleaned out so I can move in there and do work inside, I should be all set just in the nick oftime..


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