pantherpaw9

I may be incorrectly assuming that this is in response to the kerfluffle that occured previously in the post. I would like to say that I'm very sorry. I suppose I should keep in mind that not everyone appreciates or understands my humor. It was honestly an attempt at a joke, and while I will admit, I was definitely being snarky, I truly didn't intend to ruffle anyone's feathers. I should have been more respectful and appreciative of Steve7010's advice, and I should not have been such a smarta$$. So when he suggested I was being rude, I didn't respond very well to that either. I think everyone is "chilled out" now, and Pastor Gary was kind enough to step in and get us back to the discussion. This occurred over a week ago, so I'm not sure why it's being revived here now, but I thought I would at least make an attempt to apologize here now, so that we can continue with the discussion and solve the mystery of programming the M1225.

Good grief, I simply thought your response was not an answer to the question that I was asking and I was just trying to clarify what my question actually was with a little snarky humor. I thought you were being a bit kirt by suggesting I “stop mixing up the names” when in fact I am new here and simply didn’t know about the other radio names. You were so quick to jump on me for misspelling the model number of the radio, that you simply mis-understood my question altogether. So you are the one who is being rude to me sir. Good day to you

Well obviously I meant M1225, and the answer I was looking for might have read more like this: "Yes David, the radio is programmed by plugging the RJwhatever cable you saw on ebay into the front of the radio in the mic port, not the back. The 20 pin port on the back of the radio is for bla bla bla"...and isn't used for programming." Or maybe something like this: "No David, (as you suspected) the cable you saw on Ebay that looks like it has an RJwhatever plug on it, won't work, the cable you need must be a 20 pin plug that goes into the back port. You can't program the radio from the front mic port."

I do wind design for structures in Florida on a regular basis, and you would be looking at 40 psf up to 50 psf. So for 4 sq. ft. (2'x2' box) you would be looking at about 200 lbs. of lateral force on the box. Just as a general estimate. How close you are to the coast and how high above the ground you are would also make the load higher or lower, just to give you an idea. Of course any construction would need site specific calculations with local code compliance and approval. These numbers are simply for conversational purposes.

I noticed the programming cable for the CDM1225 on ebay looks to have a CAT5 type data plug on one end, and a USB on the other, but I did not see anywhere on the radio photos (back side) where this cable would plug into a CDM1225. The CDM1225 seems to have a 20 pin port in the back. Does the programming cable plug into the front where the mic plugs in??

I take it these CDM varieties will program on a 64 bit modern USB based computer more easily? Also, do these varieties meet the part 95 legal operation criteria? If they do, then maybe I would like to check these out. I just want something thats inexpensive, easy to program, has 40 watts of power, and is legal to operate on GMRS frequencies.

The M1225 is the radio I have been looking at as well. I would love to find out about the programming as well. I take it the CHIRP software won't work from reading your previous comments. Actually, I was looking to buy 2 of these radios, one for the truck, and one for the radio shack. If I like this radio and I'm able to get set up to program it Ok, then I will likely buy more of these for my dads truck and my two son's vehicles as well.

HaHa! I doubt that, but thanks anyway. I have a small advantage over most people that jump into this hobby because I have an engineering degree, but its in civil engineering, and I failed Physics 202 Electricity 2 times before the professor finally passed me because I was driving him to the brink of insanity with my questions. So I know just enough to get me in trouble as they say.

I was watching the video again, and there is an image about half way through the video that shows the squelch detector and there is a vertical dimension drawn on the modulated wave in the diagram that is supposed to represent the wave amplitude. When the term "noise floor" was introduced in this forum discussion in the previous post by Hans, I'm assuming this is related to what the video was trying to explain. I'm guessing that squelch is simply filtering out signals that are below a certain "power" threshold or signal strength. Is that correct? Is the signal's amplitude related to its "strength" or "power"? If this is true, then the squelch is simply allowing the speaker to emit voice sounds that come from waves that meet a "minumum power level" that is set by the squelch knob? In other words, it mutes signals that are not at least a minimum "strength"?

What is carrier squelch? I think I'm confused again...haha. Is carrier squelch the same as "T-Sql"??

Sorry folks, I see now that there is a very recent thread that is being discussed about this very topic. It might even be the thread I got this radio from. Anyway. I was going to just delete this thread and jump over to that one, but I don't know how to do that so just disregard this topic altogether.

I read in one of the forum posts that this was a great radio for use as a GMRS base radio at home or mobile radio in my truck. Wanted to get some opinions on what else I would need to track down to get it operational. It seems to be just the unit itself without any mic or installation wiring harness, etc. and I really don't want to create a problem for myself. Also, I would obviously need to program it so I would need to know what software and data cable it needs. https://www.ebay.com/i/233034704225?ul_noapp=true Basically I want more GMRS power (like 40 watts) in a radio that is legal for part 95 compliance. Any tips on any other good rig that would be legal to operate with more power would be awesome as well. There seems to be much debate around this topic about what is legal, so I am really in the dark here. I think the 4 watt power limit only applies to hand helds, is that correct?

Yes all my friends and family are baffled as to why I have added radio as a new hobby at 50 years old. I am absolutely hooked! Fun is what it's all about. I can't wait to get my HAM technicians license in January so I can join up with my local SOTA group and go up on the mountains and learn all about mountain top activations. I'd better start studying for my General class so I can get in on all the HF action.

That video also explained my next forum question topic, which was about bandwidth. I see now why the frequency needs a defined bandwidth to take care of the deviations from the carrier frequency. The radio is simply using the deviations from the carrier frequency to determine how the speaker should vibrate. The vibration of the microphone causes fluctuations in the carrier frequency and these fluctuations are "de-coded" at the other end so that the speaker reproduces the same "vibrations" (sound). It's brilliant! I think I'm very close to understanding this entire mystery. Correct me if I have totally mis-understood bandwidth. So when I hear people talking about how the FCC has narrowed the bandwidth allowed from 24ish down to 12ish, to make room for more frequencies to be allocated for use, this explains why the sound quality goes down. Because there is less elbow room for the audio signal to be squeezed in. So its kind of like the resolution of a digital photograph. The lower the resolution, the less detail of the original image is visible, thus effecting the quality of the image. This is really fascinating stuff.

Perfect. I'm going to You Tube on my lunch break. Thanks

That was a great explanation, and I think it just took hearing the explanation presented in a variety of ways, but I definitely understand this much better now. This explains why my radio is able to communicate with the repeater without any T Sql settings programmed. I only have "Tone" selected in my program. So, if I want to filter any and all other traffic on that frequency, (and only hear signals going through the repeater), then I would have to change my "Tone Mode" from "Tone" to "T Sql". I can read back in the thread and see now that this was explained already several times but it just wasn't sinking into my thick scull. haha

Thanks Hans. When I show up to my second HAM club meeting, I am going to blow their mind with all my radio knowledge! Hahaha

So if two repeaters are close to each other and use the same frequency, you could program each repeater into two separate channel numbers and each channel would be programmed with the different corresponding tones, subsequently allowing the operator to pick which repeater they want to use simply by changing channels?

Haha, that’s ok, I always try to throw a little humor in these threads for my own entertainment. I’m extremely grateful for everyone’s patience with my questions. I am not where I want to be in my understanding of this topic but thanks to you folks I am getting very close. I’ll keep studying on this.

So if the squelch is “stopping something quickly and completely” (in this case the something is the signal) the tones act to “un-stop” “open-up” and “un-mute” the signal and pass it through to the speaker and into my ear. I see now why the terminology was used in the previous posts, and I sincerely thank you for the explanation of the word meaning; however, I’m still confused as to what scenario would need a “tone” and what scenario would need a “T Sql”. I’m going to have to sketch this out on some paper and study this a bit more. I tend to understand diagrametric explanations better than scriptural. So, If you want to look that up in your little dictionary there, it means I like a book with lots of pictures...Lol

Well I was able to reach Sassafras repeater to talk with a gentleman in Cleveland GA today on the 4 watt TERA TR-505 and I was in Gainesville so I was about 30 miles from Sassafras and 10 or 15 miles from Cleveland. I think the problem is exactly like you explained, I’m losing contact with the repeater when the 4 watt handheld is in areas without line if sight. That explains why the radio works sometimes and does not work sometimes. I also have to keep in mind that since the Sassafras repeater is not linked at the moment there are simply fewer people listening. Anyways, my son is coming up tomorrow and he’s going to help me run some Simplex testing around the local Dahlonega area, so that should be even more educational.

Does “unmute” mean the same thing as “open up the squelch”. And if so I’m assuming both of these terms mean: “I can hear the other person speaking from the speaker of my radio”. Yes...I’m that dumb. Haha. I know that sounds like basic knowledge to most radio folk but all the radio jargon in these explanations leaves me confused. The good news is my radio is working so this is all about me wanting to truly understand how these radios and systems work.

So If I want to communicate through the repeater for a particular frequency and also receive signals from anyone locally with Simplex on that same frequency, then I would want to select "Tone". Alternately, if I wanted to only communicate over the repeater and filter out all other local simplex traffic, I would use "T Sql" If that is correct, then I think I am very close to grasping this concept. I hope I got that right, but correct me if I'm wrong.

In program softwares like CHIRP and others, there are 4 or 5 different choices for the Tone Mode column. 2 of them are called "Tone" and "T Sql" which I assume stands for "Tone Squelch". What is the difference and how do you know when to use each one. I think the other choices are for digital radios or something like that which I'm assuming I don't need so I'm basically concerned with the aforementioned 2 items for tone. Can anyone educate me on this?

Thanks again, and that sounds like it would be a great test. Let me know how it goes.