Radioguy7268

The trouble with a Carrier Squelch repeater is that it will repeat literally everything it hears. There's no real control, and if you're high up, you'll hear the world, including stuff that you really don't want to repeat. If you've got any other co-channel user close by, your repeater will be keyed every time one of their mobiles is transmitting. Not ideal, not even close to useful, and pretty much guaranteed to be a pain to your neighboring system. I don't see anything in the rules that says you have to run PL, but the FCC does say you're supposed to avoid interference and monitor before transmitting.

The biggest issue with your plan (as I see it) would be actually acquiring the equipment in today's supply shortage world. DLR (and DTR) 900 MHz Frequency Hopping Spread Spectrum radios are great for indoor coverage. If you're looking for some Rental Agreement boilerplate, dial up one of the major players and tell them you're interested in renting 10 or 20 radios. See what they send you (nobody says you've got to sign it & agree to the rental!) As someone who has a fleet of UHF and VHF rentals, I can tell you that the biggest issues are #1 - dealing with someone who has actual spending authority. #2 - getting ALL the radios back after completion of the rentals. #3 - Defining the cost of replacement up front, so that there's a responsible User in charge who will represent your interests in having the radios returned in good shape. You should also consider Gang Chargers as a necessary part of the equipment list. You'll never untangle all the charger cords on single unit desktop chargers if you include them with a stack of rentals.

Re-reading your post, it seems you're asking if we can identify the actual noise that you're experiencing, rather than the effect. I can't hear it well enough to discern what it is. There does seem to be some mixing involved. Are you friends with anyone who has a spectrum analyzer? Are you able to get an RSSI reading of the interfering signal? Does it come and go? or is it always there on your receive frequency whenever your system is idle? If it's constant, you can be almost certain that it's another transmitter on a totally different frequency that's mixing with something else nearby to create what you're hearing. Search up "2nd order intermod" to get an idea of what could be going on. Direction Finding could also be useful to pinpoint the area where the signal is coming from.

Yes - the FM Capture effect. Basically, in FM the stronger signal will win. Once the stronger FM modulated signal is about +6dB or better (stronger) than the interfering or weaker signal - you won't notice that there's another signal present, or your ear might be able to discern a slight very slight warble/wobble in the background if the interference is fluctuating right around that 6dB level. This also gets into the reason why Pre-emphasis/De-emphasis has become the standard for FM radio transmission. You can read entire books and articles dedicated to the study of FM capture. It was one of the reasons that Armstrong pushed FM as his preferred modulation method. Compared to AM - it certainly did have less static. Armstrong pushes "staticless FM" technology - Free from interference...

The rules don't say that you can't use it - but I'm not aware of any Motorola radio that's type accepted for Part 95 that has MDC signalling. "Legal" has lots of angles you can view it from. There are other brands that now offer MDC signalling.Vertex, Icom, and Kenwood all have certain models that offer it. It may not be fully compatible with all features in the MDC1200 Motorola world, but they've got it. I'm not actually sure if Motorola patents expired, or if they just decided to license it to other manufacturers at a more reasonable cost.

I must have missed the part where a willing buyer and a willing seller are involved in a transaction that becomes a rip-off. If someone is willing to buy something that's a price 3 times above what it 'normally' sells for - then that person is signalling to the market that there is a shortage of the product, and that there is an opportunity awaiting those who can fill the gap. That's economics 101. People make noise about price gouging and rip-offs. Pricing to the market is what every enterprising businessperson does - or they go out of business. If you're a consumer who pays 3 times the 'normal' price for the product, you either have a compelling reason for buying it, or you're plain nuts. Wait out that temporary price increase if you feel that the market will correct, or search for alternative products that meet your need at a price that's more appealing.

You likely don't have the front mic HUB grounded (ie: the radio thinks it is off hook). Been too long since I was into the MCS2k software, but there should be an "ignore HUB" setting or similar tick box that would work. Or, if your mic jack is open, slap a palm mic in that has a hang up clip attached.

The VX-2200 is a fine radio and a good choice for GMRS. When you go into the software to "configure" your port settings, you should probably select the lowest possible baud rate. Vertex software can be a little finicky about what works as far as cables for programming. You also need to make sure that your cable has the proper driver loaded. When you plug the cable into your mic jack of the mobile, you should get a beeping along with a message on the front display saying that you're in programming mode. Here's a little help file that Google found for me. I didn't read through it completely enough to vouch for its 100% accuracy, but it seems that he hits the main points to look out for and how to make sure that your software is communicating with the radio. https://hamradioprogramming.net/vertex-vx-2200/how-to-program-vertex-vx-2200

Sometimes, yes. They need to be properly installed, the rest of the site equipment needs to be properly grounded/bonded and protected. They are not magic. If you don't do the rest of the job right, tossing in a Polyphaser is just a waste of money. If you pay attention to the rest of the job, install the surge protection properly, you will reduce your chances of damage to something closer to zero. Search up the Motorola R56 standard. There might even be a video or two on it. It's a heavy read, but you will find out what you need to know to do it right.

I posted my Bridgecomm experience a while back. The units definitely have a problem with DPL. I would write a letter to them firmly requesting your Sales tax to be refunded back to you - and copy your State's Sales Tax/Revenue department. It's not their money to keep...

Count me as a dealer who doesn't like it much - at all. EID's - where the capability is built into the radio, and then you needed to buy a (lifetime) License to unlock that capability made sense to me. What doesn't make sense is the concept of needing to buy a Software Update Management license in order to update firmware in the radio. It makes it a real pain when you need to reprogram a bunch of radios, and you basically have to figure out where each radio is at before you can create profiles. You end up with 4 or 5 different profiles if you don't want to upgrade firmware on every single radio & purchase a SUM for every unit past warranty - even though the customer might have all the same model radios.

A Control station is properly licensed as an FX1 "Fixed Station" in Part 90. I would agree with the concept that a Fixed Station could either refer to a link or an uplink to a repeater. The FCC does a terrible job of defining the terms used in Part 95. Previous discussion here: 3523-what-is-a-fixed-station

Kind of depends on what is important to you. You would need to read through more than a few threads on here to get the gist of what people's favorites are. I could list a few of mine, but that doesn't mean they're going to be what suits you. For small, simple, cheap, and with easy to acquire software, it's hard to beat the Vertex VX-231/261. They'll put out an honest 4.5 watts and can do either Wideband 25 KHz or narrowband 12.5 on a per channel basis. If you have to ask where to look, you're probably not familiar with all the tricks and traps of Ebay. So I'd say to go take a look at used-radios.com The products and prices there are fair, and they will program what they sell.

I'd recommend a used Vertex, Kenwood, or Motorola commercial radio. Plenty of choices under $100 - and they have resale value to boot. Many online sellers will program the radios for you to the frequencies/codes of your choice. Vehicular chargers from Impact like the DC-1 allow you to plug into a cigarette lighter or hard wire a mounted charger pocket.

The Motorola 900 MHz digital FHSS radios are great for in-building coverage. They work pretty well outdoors in the open also. 1 watt is a little misleading when comparing them to "full power" UHF 4 or 5 watt portables. Transmit power is only useful if it overcomes the noise floor that you're trying to transmit over. Where those 1 watt 900 MHz FHSS radios shine, is that they have an effective receive signal level that's down in the -125 dBm range. Your typical UHF portable is lucky if it's beginning to receive anything at -119 dBm (and even if it does, then it's probably quite scratchy). So the 900 MHz radio comes in at better than a 6 dB winner in the receive category. Search that up on the dBm to Watts conversion scale, and you'll see that your UHF portable would need to transmit a decent signal at 4 watts or more just to begin achieve comparable performance - while the 900 MHz radio is hopping frequencies to avoid interference, plus pushing out a digital signal that's intelligible even at the very threshold of receive. Forget comparing horsepower numbers. In the radio world, you need to compare receivers. That's where the magic is happening. Watts are for salespeople and marketing types.

Good, Fast, Cheap. Pick any two The same could apply to radios with: Good Coverage, Low Price, Easy to Acquire. Except you can only pick 1... 20 miles reliable coverage to hand held portables is usually not going to happen with a "garage" repeater at your home location. In years past, I've seen those GR300 desktop repeaters at tower sites with good elevation - and as Gman says, they usually have a bunch of bandpass cavities, preselectors, and pre-amps wired in, which kid of defeats the whole "done on the cheap" - spending $350 for a GR300 vs. $1000 - $1500 for a used Quantar/MTR2000.

Beyond having a very sensitive (hot) front end, the Quantar was also very selective, a difficult combination to achieve. I'm surprised to hear that the Quantar transmitter at 50 watts greatly out-performed the Kenwood transmit at 50 watts. I'd have to think that the Kenwood was falling short in either Deviation or it was off frequency. Lesser radios do tend to have some frequency drift as they warm up. The good stuff will be rock steady on frequency center. The biggest thing I've noticed with Quantars (and their cousins the MTR2000) is that all the internal audio processing is done with PCM (pulse coded modulation) - so any noise or hum is filtered out, and only the audio is passed. That would effectively mean that the MTR's and Quantars were full quieting with a receive signal strength of less than .35uV (around -116 dBm) - which is where many commercial radios are just beginning to break squelch.

You might want to search up SAR - Specific Absorption Rate. 20 watts right at ear level and close to your head probably isn't a good idea. Dropping the power down to 10 watts should still get you 80-90 % of that 3 mile distance, and would be like moving the antenna a full wavelength further away.

The MTR2000 has no standard provision for changing channels. You can set up a channel steering function through the rear 96 pin connector, but it's something you would need to homebrew. There is a special handheld service microphone that was sold as a service tool, and I believe that would allow you to change channels (Nope! I just looked it up - P/N GMN6147 - it doesn't allow channel selection) and adjust station volume levels for the speaker (but you still needed to provide an amplified external speaker.) The MTR2000 is great for a single channel repeater, but it's NOT noob friendly for someone who wants to play around and figure out what works best.

Basic repeater instructions would be to program it to your intended frequencies (Transmit on the Lower frequency, Receive on the Higher frequency) - and for GMRS, make sure that the channel is set to 25kHz wideband. You would also need to let them know the specific Tone code (PL) or DPL that you plan to use. Now beyond that, there are tweaks and settings (as well as a tuning procedure specific to the MTR2000 that most hobbyists are NOT qualified to perform) - but if it's a used repeater, those functions should have already been set and tuned, and now the new frequencies just need to be programmed in, and then everything double checked on a Station Monitor. Used-Radios.com is more than capable of doing all of that, and doing it well. Unless you have some exotic use case beyond a simple repeater, there isn't all that much information to give them. Freq's along with your chosen PL/DPL, bandwidth, and your FCC call sign if you desire CWID.

Motorola repackaged a nice Celwave bandpass/band reject duplexer with most MTR2000's, although that was not the only possible "MTR2000 duplexer" that might have existed. If you have a link or more detailed description, it might help to figure out which one you're looking at. EMR makes some decent equipment, but the model you have listed is a basic "flatpack" compact mobile duplexer which is a Notch style - not the greatest duplexer for use in a high quality repeater install. Any duplexer requires tuning to operate on your exact frequency pairs. The Celwave MTR2000 duplexers sold by Sunny Communications (Used-Radios.com) for $525 include tuning. That duplexer is the real deal.

Shipping costs for antennas have become ridiculous. If it's beyond a certain length, even UPS Ground is a killer. I can't tell you what the magic length is, but I've dropped a few antennas from my "go-to" list due to shipping costs.

The Model 43 is still the tried & true standard - but Bird did make the Model 4391 Digital Wattmeter - along with the newer Model 4421 with Digital display. Both are more of a benchtop model, not the bulletproof field tech design of the Model 43. Another group I monitor - someone had posted a picture of a supposed Model 44 - which looked like the 43, but had a digital display, and was supposed to handle DMR/TDMA digital. Googling that doesn't show me any current digital offering by Bird. Could have been last year's April Fool's joke?? It does appear that someone makes an aftermarket digital display that swaps into a standard model 43. Our normal setup is to plug in a common Analog "test" channel into our mobile radios, and do our SWR and install tests based off the analog side - using a model 43.