WROZ250

Thank You!

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I wouldn't get too excited when expressing increases of power in Watts. Going from 5 watts to 8 watts (if any of those 8W claims are even accurate), is a relatively small increase in transmitted signal. So when one factors in battery drain/life and heat generation, for example, it's not really a performance enhancement. Typically, the single most detriment to the performance of any hand held radio, is the antenna. The vast majority of 'duck' antennas have far more impact on radiated signal than any power out of the PA. Not to mention antenna system loss goes both ways (receive and transmit). The ubiquitous 'rubber duck antenna on most HTs, is only moderately better a dummy load. Indeed, virtually all 'duck' antennas have losses on the order of several, even tens of dB, when referenced Isotropic dBi (perfect radiator (theoretical) verse dBd (real dipole). However, as others have pointed out, the effective radiated power out of any given HT is a balance between the convenience of operating portable and, meeting mandated exposure limits. The latter, in the case of GMRS (UHF) is quite relevant. That said, were one to hook up an 8W verses a 5W HT to identical (external and proper) antenna systems, most would find very little difference in signal performance. Again, all other things being equal. ?

Actually the computer the kid was using in the movie was the IMSAI 8080, another kit similar to the Altair, based on the 8080 chip. The monitor was what was throwing me off on the Altair idea. The latter (Altair) did not support a monitor by default.

I've seen it many times. That was War-Dialing and we all did it back then. The movie touched on a lot of the nerd stuff from the day. I seem to recall the kid had an Altair kit computer on his desk. Love, and sadly remember, the old audio coupled phone modem! The scene where he made phone calls from the ground start payphone. They didn't have him using the coveted 'Blue Box' for making long distance phone calls. A lot of the rest was total BS, but it was a movie after all. Still, it captured the spirit of the computer hobbyists of the day. How times and technology have changed.

I stand corrected, the new term for illegal access is now Piggybacking, whereas War Driving is in fact what the guy in the Reddit article was doing, which is legal. Not, I suppose, that anybody really cares! LOL!

How to say "hey, there is a lot of expensive stuff in this vehicle". FWIW, 'War Driving', at least where WiFi is concerned, is a crime ('unauthorized access of a computer network' and, 'theft of services') in most states, after it was brought to light by the arrest (felony charges) of some guy in Florida back in 2005. I should add, that after seeing the owners response on Reddit, what he is actually doing is NOT illegal nor is it technically 'War Driving'. He appears to just be collecting location data for WiFi systems. Bottom line, secure your WiFi.

I agree that 'screen room' without elaboration/details is perhaps a little ambiguous. I only know the one room type labeled 'screen room'. A room that is isolated for monitors and such, is not a 'screen room', even if it has some level of shielding. So calling an isolated room a 'screen room' is like calling an automobile an airplane (IMHO). Assuming the OP was talking about an actual 'screen room', the control panel thing would still be a no-go as any cabling, including audio/control signals, entering such a room must be filtered, as any cable can conduct RF. Indeed, it isn't what type of information is being carried but rather any 'wire' can and will act as both an antenna and a radiator. I also agree that an antenna switch used as described probably would not work because, as you mention, there simply is not enough isolation. There are switched that have up to 50-60 dB isolation between ports, but they are quite expensive. There really is no viable way to isolate a receiver from a transmitter on the same frequency while sharing an antenna. As far as the screen room thing, perhaps my responses are a mute point because, as I think about it, anyone with an actual 'screen room' would or should already know the issues. LOL! In hindsight, I can't help but wonder why the OP even mentioned 'screen room' if they don't actually have a 'screen room'. ?

There a technical solution nobody appears to have mentioned... However, before wasting your time reading, I believe you simply need to accept the suggestion of a simple antenna switch and one radio at a time. The technical possibility... Logically speaking, one probably isn't listening while transmitting. Can we assume that for now? If you want to transmit on one radio and have both radios active, a mute switch might do the job, assuming both radios are not on the same frequency. By 'mute switch', it could be a simple as a pin diode type on the non-transmitting radio that would shunt the antenna input while you are transmitting on the other radio. This would operate in a similar manner to how many radios work that do not use a relay for TX/RX, except that it would be an external device. You could have such device on both radios with a bypass switch for use on the chosen active radio. Couple of issues. #1. This would likely be a DIY project as I can't recall the last time I've seen and external device like this. #2. In the bigger picture, this is more complicated and likely far more expensive than a simple antenna switch. #3. You mentioned a screen room in your shack. I am assuming you mean an RF shielded room (a.k.a. Faraday Shield) for working on sensitive receiver alignment and such equipment where ambient RF would make such work next to impossible. Any wiring into the room, including and especially AC power, had to go through a series of RF filters to keep the shielding intact. This is a problem for any antenna solution including an A/B switch. It's a problem because the moment you bring any antenna feed into a screen room, you render the shielding inoperative (defeats the shielding). It is possible to have an external antenna, but like AC power, it is a specially designed port, usually from the screen room manufacturer that must be capped when not in use. This is, however, yet another expensive option.

It's difficult to know with all the legal double-talk in the rules, leaving it open to multiple interpretations. The internet, in its current from, did not exist when the original rules were created, and so I've always (cautiously) interpreted this as a prohibition against the, as it is referred to, "Public Switched Telephone Network". The internet is a slightly different animal, where the PSTN was/is, literally speaking, a switched analog network (albeit does in traverse trunked lines), the internet is a packet switched network. A technical but perhaps also a significant difference. Yes, this technicality could be seen as splitting hairs in pointing out that technical difference and, there is no denying the internet today, is a 'public network'. There are timed when I look at the rules as written and wonder if the feds are giving us enough rope to hang ourselves! LOL! Lastly, it is difficult to assume that lack of enforcement by the FCC is a sign that linking is now legal, because the reality is the FCC rarely enforces any of the rules these days. Perhaps their attitude about linking is not unlike their apparent attitude about other rule violations (if modern repeater linking is truly a violation as some argue) in that as long as it isn't causing problems for other licensed services, it's not a problem worth their investigating. Just an observation/opinion.

Let also not forget the expense repeater operators go through to construct and maintain a repeater! I'm not talking about a couple KG-1000 mobiles with an amazon duplexer, rather a full blown commercial grade, wide area, repeater at a tower site that may or may not have rental fees. It's not cheap by any stretch, and if a repeater operator wants to ban someone, they have every moral and legal right to do so. Be thankful most of us simply do it for free and only ban troublemakers.

To be clear, I was absolutely not dissing Bird (I own one and love it). My point was regarding the OP's comment about 1.00:1 vswr. Specifically, even a Bird meter will almost always display some reflected power even while on a dummy load. There is always some margin/percentage of error with any measurement even with the best test equipment, ergo, always question a 'perfect reading'. :-)

Agreed, but even a Bird has a margin/percentage of error in a reading. It's typically posted on the back of the meter.

Personally, I would question any reading that suggests no reflected power. Even a quality dummy load will normally have enough of a mismatch to make the meter 'twitch'. The possibility of a 'perfect match' is highly unlikely. Another factor is the meter's range setting. If you measure a 5W transmitter with a 50-100W setting (or slug with a Bird meter), you're not likely going to show any reflected power on a close match. The reason being is that vswr is a ratio measurement. Additionally, where the meter is located in the antenna feed will also affect the reading. It's possible to have, for example, an antenna with a 1.5:1 vswr, as measured at the antenna. However after 100ft of line, the line loss measured at the transmitter will normally cause the vswr to read far lower. Not saying such a 'perfect reading' is impossible to obtain, just extremely unlikely.

DMR is, at the fundamental level, still FM radio. Yes, the way the signal degrades with range is better than analog FM, but the overall range is about the same. It is simply that the digital tends to maintain voice quality better than analog until the dropout point whereas analog quality degrades semi-linearly as the distance increases. The perception of range, all things being equal, appears better with digital. If there is any real valid reason to allow digital, in the case of DMR for example, it is the ability for a repeater to provide 2 radio channels (using two time slots) on a single frequency, of which two simultaneous, separate, conversations can take place at the same time. Basically doubling the available 'channels' This is true for subscriber units as well. All that said, it is unlikely the FCC will consider digital for GMRS anytime soon. One would think if that were the case, they would have done it with the last major revamp a couple of years back. Will/Could it happen, sure. But I wouldn't hold my breath. Even if the FCC were to do it, it brings up another, perhaps bigger issue that other posters have pointed out. There are many GMRS users now who struggle just to program their existing analog FM radios, others still who don't completely grasp the concept of basic repeater operation and things like CTCSS or DCS. I can say with a bit of authority that programming a DMR radio isn't something the average GMRS user is capable of doing, at least not without assistance, as it is many times more complicated than configuring analog FM radios. Compound that with proper usage of DMR. Also, things like who ensures that digital IDs are not duplicated? IMHO, adding digital to GMRS has many potential pitfalls, the least of which is the FCC granting permission to do it.

Absolutely, most controllers have that option/ability. Many of the cheaper ones don't even have a CWID!

The CM108 and CM119 interfaces are absolutely the best! I've yet to finish a FOB conversion but do have the RIM Lite version 2 from the Repeater Builder guys and it is fantastic. Bit more expensive than converting a sound FOB, but probably the better route in the long run (IMHO). Unless you're talking a good used deal, those WYSE thin clients are pretty pricey. FWIW, Canakits still has Pi4 available and compared to the WYSE Thin Client, the Pi is actually cheap. That said, almost any old PC with Linux will work for a repeater controller. However, the Open Repeater project is strictly Raspberry Pi right now and only the original Asterisk (AllStar) software is available for Pi. The Hamvoip version of Asterisk(Allstar) is newer, but like the Open Repeater, is only available for Raspberry Pi (unless one likes compiling source code). All that said and, as I commented previously, there is always the option of another I20R or Motorola RICK and, I believe there are a couple of super cheap options that are available such as the Surecom SR-328 duplex controller which, last time I checked, was well under $100 (USD). There are a lot of options depending on one's needs, abilities, and budget.

You have a lot of options, the big three that come to mind are the Open Repeater Project, the Arcom RC-210, and even the AllStar (Asterisk) software, all of which can be configured to have no tones or CWID, if desired. The latter (Asterisk), will act as a repeater whether it is connected to a network/internet or not (i.e. stand alone repeater). BTW, most 'repeater controller' use tones when generating the CWID. I assume you simply do not wish to send a CWID? None, unfortunately are 'cheap' with the RC-210 being the most expensive and the Open Repeater somewhat cheaper, given it can be built on the smaller Raspberry Pi (W). Allstar can be run on a Raspberry Pi 3 or Pi 4 or, a Linux PC (if you have an old, working, PC laying around), so the cost varies. Another option is to simply build a COR to control PTT and an audio interconnect. Lastly, there is always the Motorola RICK and even another i20r if you hunt around for a used one. There are other repeater controllers on the market as well.

I downloaded the GMRS img file that was posted a few months back. However, I have a question... Is this RPi image really all that different from the ones used by Amateur Radio's Allstar image or, are there just a few network related parameter changes in key configuration files? I ask, because after recently building an Allstar repeater with the RPI 3B+, it seems a relatively minor effort to change the network servers in the config files from a working Allstar config system to those used for GMRS. Seems like duplicating/cloning a working image and simply changing the required parameters rather than start a new build from scratch would be easier. Just curious.

It is quite and likely possible that they are NOT operating illegally. Many businesses had their licenses grandfathered and so are still operating legally on GMRS frequencies. Now that said, it is also possible they have let their former license lapse. In any event, it is never a good idea to confront whoever you believe may be operating illegally.

Surecom concerns aside, the DB-25G (nor any of it's relabeled cousins) does not put out 25W, regardless of the advertising. I have three variants of this radio, all 100% identical save for the label and they all pretty much put out ~18W max at 13.8 Vdc. That said, it's a pretty decent radio for the price (~$100 USD).

Should be interesting! the orbital data shows the passes that at some point will cover pretty much anyplace on earth. BTW, I found this one on the Heavens Above site by searching for the NORAD ID (43881). https://www.heavens-above.com

https://www.n2yo.com/satellite/?s=43881

Of the current crop of (VHF, UHF, and UP) digital voice protocols, the waveform is polarized to a large extend and a linear translator such as those used on current satellites will invert whatever passes through it, both in data polarity and frequency. The latter exacerbated by any Doppler shift. Even a shift of a few hundred hertz is enough to send the BER soaring and so nothing gets received. The problem, even without Doppler, is that losing or corrupting any part of the original signal will result in errors. Dropping to baseband might pass the voice portion (might), but you would have none of the rest of the data that isn't contained in the baseband, and so the signal is unreadable by a receiving digital radio. These protocols were simply not meant to be used in this particular application. BTW, the reason packet works is because it uses tones for mark and space rather than a pure digital waveform and, it processes the packet before before generating and sending a new response packet. Other 'digital protocols' like PSK and others, possibly even FT8, might actually work through an FM or LT type satellite because it is basically audio tones and, the actual received signal can be anywhere within the application pass-band (e.g. Doppler and phase have less impact). All that said, I'm pretty sure the regular satellite operators would be pretty miffed to hear even those signals coming through the satellite. ?

Impossible to do through an FM or an SSB (linear translator) satellite, given the nature of digital voice technology (DV). The latter, (Linear translator) might actually result in a DV stream on the down-link, but all of the data would be inverted and/or distorted (not to mention the Doppler impact), resulting in gibberish that could not be decoded. Early on in DV, a lot of people thought you could hack a mobile and simply feed the discriminator out on a DV receiver and feed it into the modulator of another DV radio's transmitter, which doesn't work. Actual DV repeaters do not simply send base-band from the RX to the TX as with an analog FM repeater. Even if one were to take the raw speaker audio and feed it to the microphone of another radio, it would not work. Yes, something that sounds like digital would be transmitted, but it would not contain the information from the sending radio. DV is not analog. At best, a simplex repeater device connected to a DV radio would perhaps parrot the voice information, but all other signalling would be lost. Indeed, virtually all of the mainstream digital voice technologies, DMR, D-Star, P25, etc... essentially decode the digitized information from the receiver, process it, and then re-encode it for the transmitter, hence the slight audio delay on digital systems (in the case of repeaters). Because of that, in the very early days of DV, many of the D-Star advocates argued that their repeater wasn't actually a repeater at all, but rather a 'store and forward' technology, in an effort to bypass repeater coordination and frequency restrictions. One such advocate, convinced the idea was valid, posed the question to the FCC to 'settle the debate', which resulted in a all of systems that had subscribed to the (not a repeater) idea and, had constructed systems outside the legal repeater sub-bands, were ordered to shut down. In any event, unless a satellite was specifically equipped with a DV repeater, which today is not out of the question technically, none of the current crop of digital voice technologies would be retransmitted (repeated) by any of the currently active satellites. All transmitting into a current satellite using DV technology would do, is jam the other users. :-| BTW, a perfect example of why DV through a satellite can't work... try using DV through an analog FM repeater.