Premature, short, non-comprehensive and probably flawed very early review of the MicroP25RX:

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AuggieActually

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Very short version:
RF performance: Spectacular
Audio performance: Good
Ease of use: Better than most
Ergonomics: Needs improvement
Summary: Buy it! if you're an advanced user that wants best in class performance and doesn't mind the quirks that naturally come with a product like this.

Slightly longer version:
While I haven't nearly had time to truly test the MicroP25RX, the initial rf performance is hugely impressive. It easily bests my BCD436HP on weak signal multicasts simulcast (thanks maus), and also with strong signal multicast simulcast distortion. It's able to easily pull in a remote site with the included antenna and no external filtering that I have to use base antennas, high end filters and a good pre-amp with my Airspy to reliably tune for SDR software to pick up. I can't rule out a this as a fluke (ducting, perfect conditions, etc) just yet, but it's massively impressive. I haven't needed to fiddle with gain, agc, pre-amp, anything.

The audio performance is good with caveats. There's a background noise during audio decode with the included headphones that is harsh. Using a set of nice over the ear cans dampens the sharpness a bit, but plugging in an external speaker makes it completely acceptable. Note this is different than the white noise from the "keep speaker awake" setting. Turning down the volume on the included ear buds also helps quite a bit. (It took an embarrassing amount of time to discover this, btw). Audio decode of P25 itself is impressively clear, very understandable. Definitely a step up from the BCD436HP and DSDPlus, I'd put it on par with OP25.

Putting my local systems on this was as easy as copying DSD .sites and .groups files to an sd card (I used my own, but you can also directly download from rr) and telling the MicroP25 to import them. Also, there are .csv files for zip code searching etc provided from BlueTail that are just copy and pasted. I was literally up and running in less than 5 minutes. Easiest setup I've ever done with a scanner or software.

The screen is awesome, responsive and easily legible. No lag on button pushes, etc. Boot time from plugging in to receiving audio for the whole system is roughly 4-5 seconds, which is a welcome surprise for anyone used to P25 capable scanners.

The weak points:
The included case: It makes pushing the button upwards a difficult process. The case design also results in removing the sd card turning into an annoying process in that is just easier to disassemble the thing just to get the card out. The case quality is pretty good, very sturdy. It is likely more sturdy than needed, with a fair amount of slack space that seems to be for the latching mechanism. There's definitely room for improvement here.

The cable attachment points are also a future point of failure. The cables are completely unsupported, which means a few tugs, drops or other mishaps is going to cause issues sooner rather than later, especially with the micro-usb connector. The good news here is repairability looks to be top notch, as long as you have basic smd skills. Even if you don't, the cpu board looks like a bog-standard Teensy 4.1, so with a few (30 some) through hole heats, you can replace the whole thing. Genius use of the Teensy, btw. I never would have thought to use it like this.

Another point of friction is the user interface. While it's miles ahead of typical scanners, there's still lots of room for ease of use improvements. Adjustments such as volume control, talkgroup following, and zone control are all in different modes. While I don't have anything against nested menus, the four-way button is annoyingly both difficult to finesse and overly sensitive at the same time. It's really easy to press the button while trying to move in a direction, and to move in a direction while trying to press the button. I think with a bit of practice and a few ui changes, this will cease to be a problem, though.

It feels like I'm being overly critical here. This thing is a small marvel, it's massively impressive on multiple levels. And that's without considering the price that seems so low it almost feels like stealing. There's a very solid foundation, good design choices, and so much potential. The negative issues all seem to be easily remedied, with most of them being very low hanging fruit. A well designed case that includes battery and speaker with reinforced antenna mount will make this thing near unstoppable. From my very rough and probably wrong calculations, a pair of high quality 18650 batteries should be good for 12 hours with a moderate speaker.

Conclusion: This is awesome. Even if it never gets a firmware or form factor update, it's very useable as it is. This may be best in class hardware. Todd, you should be proud of this product. I'll be buying another at some point in the near future.

Proof that I have it on-hand:
PXL_20221118_145759569.jpg
 
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maus92

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Can you describe the relationship of your monitoring site to the transmit sites: terrain, distance, etc. Also, you are monitoring multicast sites and not simulcast sites, correct? Would modestly powered computer speakers help with the audio by reducing the source audio level, then amplifying the less noisy lower powered output?
 
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AuggieActually

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Can you describe the relationship of your monitoring site to the transmit sites: terrain, distance, etc. Also, you are monitoring multicast sites and not simulcast sites, correct?

To the best of my knowledge, this is true simulcast. There are mutiple towers all simultaneously transmitting the same signal on the same frequency.

For this inital usage, I'm inside a metal building, with the closest towers for each system at roughly 1 mile, 3 miles, 12 miles, and 20 miles away, depending on the sytem. Terrain is such that I do not have line of site on the two farthest, with small hills and fairly heavy treeline between. Some of the frequencies are close together, such that a close by tower often stomps on the weaker signals when using SDR software/low cost spectrum analyzers. It's the Ohio MARCS system, if you want more details.

As for the speakers, I'm currently using a small bluetooth speaker with an aux cord, no noticeable noise at all. Very clear, except when the signal isn't strong enough on the faintest signals.
 

maus92

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In your original post, you mentioned "strong signal multicast distortion" and not simulcast (multicast is a single transmit site); that's why I was asking for more clarity. Can you mention the specific site on MARCS? I'm interested in the site density, which I could map out if you could provide the exact site number / name. And thanks for the additional info on distances, building construction.
 

maus92

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Thanks - I also think you audio quality comparison is a useful metric.
 

KevinC

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Video? At least I can live vicariously through yours since USPS is useless for me. :p
 

AuggieActually

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Just a quick update since I can no longer edit the top post.

I almost certainly encountered tropospheric ducting when first trying out the MicroP25. The remote site that I normally can marginally receive with an airspy was coming in loud and strong with the Micro, but I have not been able to replicate this since then. So the rf performance was overstated in my original post.

Sensitivity seems to be somewhere between an Airspy and a BCD436, which is closer to being in line with expectations. Strong adjacent signal rejection is better than the Airspy, at least when using it with DSDplus. The P25RX-II is a bit better, at least in the 800MHz spectrum.

Still trying to quantify performance a bit more objectively.
 
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KMG54

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I will say living in a high simulcast area DSD+FL is good but still fumbles. The p25micro does not. Great radio.
 
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