Kd1mu Radio

02/01/2026

I started with 100 20AH batteries and I am down to 14. Now is the time to buy. High quality batteries manufacture for me by MVVTON that are only available on the Kd1mu Radio Store on Amazon.

UN 38.3 safety certified
High quality cells that delivery full power
With 90% after 2000 to 3000 cycles.
Lightweight shrink wrap over hard foam board
Power Pole connector
Custom adapters available from the Kd1mu store
5.1mm X 2.1mm charging port
Companion chargers available.
40 amp power plate for reduced resistance
40 amp BMS for added power output.
Recommended 20A to 30A continuous current
Fits in a go bag
12.8 volt nominal voltage.

12/21/2025

Already found two hardware issues with the sx1262 hat board. 1. The CS (chip select) is supposed to be connected to either CE0 or CE1 to select the SPI device. It is connected to one of the data pins, so I am doing CS in software using that data pin. 2. The RF SWITCH (between tx and rx) does not appear on the board. I wrote to WaveShare about a work around, but my plan is to hardwire it to the expected pin. he board comes with an extender header so I will test it using that. I plan to put a single row header on the Chip pins (to the left) and jumper it with a dupont single pin connector.

01/18/2025

LiFePO4 batteries are now on sale for 50% off ($55 for the 20AH). The 20AH battery is capable of delivering 40 amps but is designed for 20amp continuous use. Weighing just under 4 lbs., it is perfect for your go bag or backpack. I plan to use them for POTA activations in hard-to-reach places. Ships from the U.S. to U.S. states and most U.S. territories.

Constructed from 18650 LiFePO4 cells for safety.

Available on kd1mu-radio.com.

01/18/2025

Value-add Our Business Strategy / I get asked now and then about the differences...Read More Gregg LebovitzDecember 2, 2024

09/23/2024

Update on the store website. We managed to get started on rebuilding the website. Unfortunately, we discovered that accidentally deleting the website deletes the associated backups. We are now taking snapshots and uploading them to the cloud. The store itself is safe as it is a separate platform. It is available on my blogger site at https://www.kd1mu.com/p/store.html.

I’ve started looking into battery charger repairs for some of my baofeng chargers. I tried to buy a charger for my DM 1801 DMR radio, but the ones they shipped me did not work. They would charge, but were unable to detect when the battery level falls. A working charger using the hc5812 chip will....

09/22/2024

How flexible is your antenna? Is it flexible and have a low SWR? Does it resonate in the ham bands? My does!

09/21/2024

Without getting into details, kd1mu-radio.com is down due to website issues which may take some time to fix. The store is still reachable through kd1mu.com.

We will be making a new announcement and launch once we are back.

All about Ham Radio and DIY electronic kits and projects.

09/19/2024

Repost from my personal account.

It’s fair to say that I am a radio aficionado. I currently own 14 handheld dual band radios and one that is UHF only. The majority of my rad...