Stylophone Site Redesign!:

The work to complete the new extra pages has been delayed. I had hoped to have completed the pages by now, but sadly life has got in the way again. I now hope to have the site completed by the end of 2026. (no guarantees!)

Check it out: Norm's (redesigned) Stylophone Site

Why create this page?

The Motorola Handi-Pro Euro446 Radios are pretty nice little radios, but there is almost no technical information about these radios anywhere on the net. (believe me, I've spent hours upon hours searching)

This page is hoping to correct that. I shall be sharing information I have gained by using and playing around with these radios, and hopefully as this page becomes known, readers like yourself will be able to contribute too. Any small nugget of info you may have could be the key to bigger things, so please contact me using the link above and I'll be happy to hear from you.

The Charge Bases for these radios (model: ENLN4030A 9vAC 1200mA input) are going for ridiculous prices on auction sites, often upwards of £35, which I simply refuse to pay. So, I worked out the pin-outs and made my own charger circuit. Since the battery packs are either Ni-Cd or Ni-Mh, the charge circuit can be pretty basic. You can easily find 4.8v NiCd/NiMh charger circuits on any search engine.

Here are the Pin-outs of both the battery charger and radio:


Here is the battery diagram:

These batteries are easy to split apart and re-cell, but the thermistor MUST be installed or it won't charge in the original Motorola charger. And being a fast charger it can get the cells pretty hot, so its a good idea to have the thermistor.

Strangly, this is an all too common problem with these radios, nearly every one I've tried had some kind of fuzziness with the incomming audio.

There are 2 main causes for this, the first is fixable, but sadly as yet I have no cure for the second.

Firstly, dust and muck can get into the speaker grille, which can inhibit the speaker and make it sound buzzy, fuzzy or just quieter than it should be. To fix this, you need to open the radio, remove the speaker and clean any debris from the speaker and radio case. Sometimes spraying contact cleaner or isopropal alcohol into the speaker grille will help to wash out the muck, but its best to clean it properly if you can.

The second cause of speaker fuzziness is that the radio is slightly off frequency. There are no adjustments inside the radio, so unfortunately you cannot re-tune it. Somewhere out in the Motorola wilderness there will be some kind of tuning software, but as yet this has proved harder to find than rocking horse manure. If any of you know more about this, please don't hesitate to contact me

UPDATE 24/08/2024: I've recently got one that is bang on frequency on transmit, yet the receive audio is still fuzzy. Of course, the receive could still be off freq, but, as there's also a pretty dominant 'crack' when the squelch opens, I'm beginning to think there could be a problem with the audio amplifier or its related capacitors... Investigations will begin when I get both the energy and the time.

Here are the spkr/mic pinouts and how the microphone is wired. The speaker is connected straight through, the Mic/PTT circuit is shown below.

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More Comming Soon...