SteveShannon

The FCC ID is AFJ289402. Also these are intrinsically safe radios, which I thought interesting, although I have no need for this.

I’m looking at a pair of Icom F4161DS handheld radios at an auction site. They’re NXDN and I might be interested in playing around with them. I’ve got a three days to decide whether to bid on them or not. Do any of you here have the necessary software?

Moved to new thread.

But doing a damned fine job of it!

If your two radios are close to each other when you're transmitting on one, the other may be de-sensing, which is what happens when a nearby transmission overwhelms a receiver. Give one of your radios to a friend and have him go across the street and then see if he hears you through the repeater.

Absolutely he would need guys. But I understood him to say that he has a single 40’ mast that’s 1.25”. Maybe I misunderstood that, but if it’s true his entire mast will flex. Mid-guying would be necessary, but all guying increases the vertical load as well. You have a push-up mast that has a larger diameter base. So the bottom sections are much more rigid.

From the CDC: https://www.cdc.gov/niosh/topics/repro/nonionizingradiation.html If you are pregnant, exposure to nonionizing radiation is usually not hazardous to you or your unborn baby. However, there are some specific workplaces using nonionizing radiation that could increase your chances of having a baby with a birth defect or other reproductive problems.

Welcome! A great way to learn is by listening to scheduled nets and then, when you’re comfortable, join in. You’ll do just as well as we all did.

I can’t weigh in on mobiles yet, but I set my handheld to display multiple lines rather than two channels.

If you’re that close to the repeater you may be able to listen to the repeater input frequency which is probably 467.550 MHz. Then, if someone uses the repeater you can scan for the input tone.

Look to see what your settings are for ANI.

Goodwill is a huge 501(c)(3) charity, not a “for profit” company. Here’s a link to their most recent 990 form: https://www.goodwill.org/wp-content/uploads/2022/12/GII-Public-Inspection-Copy-990-990.pdf

My wife has had maybe 40 of these (MS and they used to track the progress by scanning multiple times, with and without gadolinium enhancement) and I’ve had 3 or 4. I always wonder which of those sounds mean I need to hold my breath. You can’t hear it very well on that video, but the background sound that sounds like a fetal heartbeat is what I imagined/misunderstood you were hearing on the radio.

That’s really the important thing!

Thanks! That’s a thought. As I recall, maybe incorrectly, the characteristic sound of an MRI is from a compressor used to supercool magnet coils. I don’t know if the compressor is inside the magnetic shielding or how that all works, but maybe the VFD for the compressor is causing problems. Anyway you look at it RFI within a hospital could be bad.

Very cool, @Lscott! It would be great if the antenna manufacturers all provided EZNEC models of their antennas. I’m thinking it the DB404-B and how the folded dipoles can be rotated on their mast to accomplish exactly what you’ve illustrated.

No RF should be able to be heard through the shell. According to the article I linked, RF should be shielded to 100 dB, but according to the OP, something recognizable as RFI matching the sound of the MR scanner is being received 3/4 mile away. Just for curiosity’s sake, can you ask the gentleman if that sounds right?

Another thought. I wonder if the communication system in the MRI uses an FRS radio on that frequency and you were simply hearing it.

It should probably be reported to the MRI department. If it’s a shielding problem their techs or someone else might be exposed to too much RF. I don’t know if that’s a concern, but I notice that they go into a separate room instead of staying in the room when I have an MRI. Here’s an article on the RF shielding that’s supposed to surround an MRI machine: https://mriquestions.com/why-rf-shielding.html

The elements are light, but they’ll have a wind load normal to the strongest axis of the fiberglass mast. A 40 foot fiberglass mast at 1.75 inches will be very flexible. Even just the elements would make the mast sway in the slightest breeze.

The comprehensive data sheet refers to the included mast as a reflector: https://www.commscope.com/globalassets/digizuite/262253-p360-db404-b-comprehensiveexternal.pdf Frankly, I think it's too much antenna to put on the top of a single 40 foot fiberglass pole that's 1.75", even with a heavy wall.

Every one of us at one time or another has either asked or attempted to understand the science of antennas on handheld radios. This video, by a well known ham radio antenna manufacturer, simulates a quarter wave antenna, held at ear ? height and illustrates the gain. It’s a short video and doesn’t go nearly far enough, but it’s interesting and could be a starting point for more in-depth conversation. The simulation software Callum uses is freely available here: http://gal-ana.de/basicmm/en/#180 And here is a video tutorial for how to use the simulator program: Finally, here’s the video on small antennas:

I can understand that; I had to look at the UV9R, UV9R Pro, UV9R Plus, and UV9R Mk1 to find the one that looked like it was the same as the UV9G. The GT-3WP that @wruu653 posted appears to be the same radio as what I posted, but in a 5w version rather than 8w and for 30% lower cost. Fortunately, Amazon has easy returns. ?

The Baofeng UV9R (ham) and UV9G (GMRS) appear to meet your criteria. Both share the BL-9 battery and it looks like they both use the 328 Moto jack. https://www.amazon.com/dp/B098JGLWZ1/ref=emc_b_5_i and https://www.amazon.com/Mirkit-Waterproof-Handheld-2200mAh-Portable/dp/B082Q1VL5Y/ref=sr_1_1_sspa?crid=3TV0O3YBECTEG&keywords=baofeng+uv-9r&qid=1675951266&s=electronics&sprefix=%2Celectronics%2C630&sr=1-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFHTkdOVFNQUVdZWEcmZW5jcnlwdGVkSWQ9QTA0NTE1NjQzTTlXRVBUNjhQMlRHJmVuY3J5cHRlZEFkSWQ9QTA5NzE4NDcxVjRRSjIwTFJBSjlCJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

I have the FT-65 as well. I really like it. I have it’s little sister as well. Both can easily be opened up for GMRS.