Astron SS-25M Power Supply Minor Repair

Astron SS-25M Power Supply

I’m an Amateur Radio operator and have all manner of short wave radios.  Most of these radios require an external power supply to function.  Generally, the voltage requirement is around 13.8 volts DC.   Additionally, some of these power supplies can be pretty pricey.  This quick entry will be about a score I made recently on Facebook Marketplace.  I picked up an Astron SS-25M Power Supply for almost nothing.

Did I get a deal, or did I get taken to the cleaners?  Let’s find out.

When I saw the ad I didn’t hesitate.  I knew even if it were not functional that I could fix it.  So I took a chance.  When I received it, I quickly powered it up and noticed the output power was rock solid at 13.8 volts.  Sweet.

The On/Off Switch LED was flickering and that could be anything from the lamp in the switch itself to a current problem.  But the output power was solid so I figured it was the lamp.

Then I tried to install it and that’s why I realized I was able to score it for so cheap.
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Best DMR Radio For 2024

Digital Mobile Radio, aka DMR Radios are expensive.  If you are a Ham radio operator you can get a hand held radio that is decent for less than $50.  Not so much in the world of digital hand held radios.   The radio that seems to be ordained for the top slot costs around $329.  John’s Tech Blog has ordained that the best DMR radio for 2024 is the Retevis RT3S which costs about $86 for a non-GPS version, and about $90 for the GPS version.
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SharkRF OpenSpot 4 Pro Review

SharkRF Openspot 4 Pro

I bought a SharkRF Openspot 1 in around 2018.  So I have been a long time user of SharkRF gear.  I absolutely, positively did NOT need another DMR hotspot but I sprung for the SharkRF Openspot 4 Pro anyway.

Boy I sure am I glad that I did.

I am no hotspot rookie and currently have 4 Raspberry Pi with various MMDVM boards in rotation here at Casa John’s Tech Blog.   I run Pi-Star and WPSD OS’s.  And have toyed with various other OS’s over the years.

There are strengths and weaknesses in all these DMR hotspots.  One weakness in the Pi-Star world is that it needs to be shut down elegantly.  When you have a hotspot plugged in a USB port in your truck which uses your cell phone for internet it is kind of hard (and very inconvenient) to find the IP address, open a web page on your phone and shut it down.  Sooner rather than later you are going to corrupt the SD card on the Raspberry Pi if you just kill the power.  In fact I have done this a few times.

The SharkRF Openspot 4 Pro caught my eye because it is battery powered.

And that is all I really wanted for my mobile hotspot.  Something I wouldn’t kill from uncommanded shut downs.

What I got was so much more than I expected.   Read on.
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Best DMR Hotspot

DMR Hotspot

So you have decided to take the leap into Digital Mobile Radio (DMR).  DMR uses the internet as the backbone for carrying communications.  Adding an MMDVM board to a Raspberry Pi is one common way to create a hotspot.

To get to that backbone you need to enter the internet either through a DMR Repeater or through a DMR Hotspot.

A hotspot is just a gateway to the internet and your radio talks to the hotspot and then your transmission is carried through the net to someone else’s repeater or hotspot.

I’d be remiss in not pointing out that so far no radio companies have really jumped in this market.  You would think that the big dog radio manufacturers that sell DMR radios would also produce DMR Hotspots, but they really don’t.

It is mostly amateur operators who design and produce MMDVM boards and sell them to the public.  You then roll your own.  There are a couple of exceptions here as Bridgecom Systems sells pre-configured DMR Hotspots.  Also, a company called Shark RF sells a hotspot called OpenSpot.  Both are kind of pricey.
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GMRS And Ham Radio Programming Using CPS

I think there may be a perception by non-radio users that us Hams simply buy radios and just push the microphone or Push To Talk (PTT) button.   If only it were that simple.  In this day and age most radios come with a hunk of software called Customer Programming Software or CPS.  With that CPS software, the user must create something called a Codeplug.  The Codeplug must then be uploaded to the radio.  This usually entails having a programming cable.  The programming cable almost never comes with the radio and must be purchased separately.  I swear that I will never understand this.

The first time you look at a CPS program it is just a bit intimidating.   So many fields to populated with information you may or may not know about as a new ham.

And I’m mostly talking about analogue radios here.  When I bought my first DMR radio, a Connect Systems CS800, I had no earthly idea what to do next.  I started looking a Codeplug to download.  The problem with that is your Codeplug is pretty specific to your local area.  Subsequently, It should be programmed for your local amateur radio repeaters. For digital radios it will also include your favorite talk groups.
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