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Showing content with the highest reputation on 05/05/20 in all areas

  1. Sigh... wasn't letting me add the JPG. https://i.imgur.com/mVih2uV.jpg
    3 points
  2. n4gix

    GMRS study guide

    Randy most surely knows the history of GMRS! After all, the very first personal use repeater in the US was his... Source: https://nsea.com/nseainfo.htm
    1 point
  3. Wow... this is perfect! I couldn't agree more, with all of this. I can't understand for the life of me, why the FCC would have two distinctively different services, sharing frequencies. They didn't even bother setting a primary and secondary service.
    1 point
  4. You have some good points marcspaz. About it being market driven, wide band verses narrow band, could get a boost by the manufactures. If they are already narrow band compliant it would be a marketing incentive for them to point it out to customers. Second any wide band equipment only, mostly used, would be eliminated from the market. Now users are pushed into buying more from the narrow band new equipment market and less from now smaller compliant used equipment market. On the regulation front manufactures could point out to the FCC they have good sales of their narrow band radios and few requests for wide band equipment. The FCC could then infer the consumer has a preference for narrow band equipment, or at least don't find it a limiting factor in how they use their radios. Making a decision to go narrow band for GMRS would be an easy one I suspect for the FCC. On the engineering side of things it's rather a screwy situation where you have two different radio services assigned the same spectrum but with different technical specifications for bandwidth. If the goal was really to allow the two to interoperate the FCC screwed it up. Having one station on frequency running wide band and another running narrow band results in some annoying messing around with the volume control. It's either to loud or too soft depending on who is doing the RX'ing and the TX'ing. By the way this happens with DMR when people don't get their audio levels set right. One minute i can hardly hear one station and the other station blows be out of the chair.
    1 point
  5. I would second that suggestion, Lithium battery. Specifically I would recommend a LiFePO4, LFP, battery. They have the safest chemistry out of the common Lithium battery types, light and reasonably high energy density. One other advantage to LFP batteries is the terminal voltage. At full charge they are around 13.3 or so VDC, a very good match to most mobile equipment that expects 13.8 VDC. The battery has a very flat voltage verses discharge curve so when the terminal voltage drops to 12.8 VDC the battery is almost completely discharged, like around 80 to 90 percent of the rated capacity is used. Don't try this with a lead acid battery. I've also found they have a very low self discharge rate. You can charge them up and let them sit for months and the terminal voltage hardly drops. For an Ecom application this would be an advantage. I've wreck enough Gel-Cell lead-acid batteries over the years I won't buy them anymore if the equipment can use the LFP type. Lead acid batteries don't like sitting around unless they have a trickle charger attached and don't let them sit around at less than full change, they will sulfate the plates. Neither of these conditions hurt LFP batteries. As a matter of fact one recommendation for long term storage of LFP batteries is to discharge them to around 50-80 percent of capacity, they can stay that way for months to a year or more this way without damage. While LFP batteries are much more expensive than the common lead acid type once you ruin a few lead acid batteries you'll get sick of replacing them and the cost adds up. I've had good luck with the following company for LFP batteries. https://www.bioennopower.com/collections/12v-series-lifepo4-batteries If you want to use a solar panel to recharge the battery a small MPPT controller designed specifically for LFP batteries is required. I have several from this company. https://sunforgellc.com/genasun/ I have a couple of the GV5 charge controllers, a good match for a 50 watt solar panel. For solar panels I got some from this company. https://www.renogy.com/products/solar-panels/ I have a couple of their 50 watt mono and 1 of their 30 watt mono panels. The build quality is good and they do guarantee them. On solar panels from my experience don't expect to get more than around 70 to 75 percent of the panel rating, which is derived under lab conditions, which you won't get in the field.
    1 point
  6. Line A and Line C restrictions were removed from the GMRS rules proposed in the WT 10-119 Report & Order. Next Thursday is the FCC meeting to consider the R&O. GMRS operators still are not allowed to communicate with foreign stations, so I asked the FCC to exclude Canada from this restriction just like they did for CB radio in the same R&O. Basically there is the same service on the Canadian side (slightly different rules, no licenses) so there's no actual interference anymore. Back in the day these frequencies were for public safety and/or business use in Canada so it would have caused problems. Now, it's almost the same service and type of users so there's no reason to keep the ban in effect.
    1 point
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