Thursday, September 17, 2020

Radio Shack/Sangean Replacement Speakers Available

 Hello folks. Those of you who want to revive your radio's sound can purchase a replacement speaker for $24. Shipping in the US is free.

 


 Speakers available for:

  • ATS-909
  • DX-398
  • ATS-606
  • DX-399
  • ATS-505
  • DX-402
  • 20-629

The speaker requires replacement if the volume of your receiver is low and the audio distorted with a crackling or buzzing sound. Radio Shack no longer carries this specific replacement anymore, but I have a limited quantity of replacement speakers from a different source.

These speakers are manufactured by a different company with the same dimensions and audio characteristics of the original speaker. They are a direct replacement and fit inside the radio without modification or damage.

 If you don't feel comfortable opening your radio and using soldering tools, then let me do it for you for $35 plus shipping.

Feel free to contact me for details.

Thursday, May 21, 2020

Radio Shack DX-398 / Sangean ATS-909 Mods Part 4 - IF Out Mod

I am excited to share an important update with you. I will perform an IF mod to the 909. Does TP11 sound familiar? Stay tuned to this post for updates. We will use the similar location that RadioLabs used for their external FM antenna jack on the back of the receiver.

Monday, May 4, 2020

Radio Shack DX-398 / Sangean ATS-909 Mods Part 3 - Tuning Knob

The next part of this series covers the rotary tuning knob. The DX-398 has a good tuning knob, but it has an unwanted feature causing it to stop or "click" in small increments. It is hard to spin the dial freely while tuning for DX. This is due to the plastic notches or detents in the tning shaft that mate up with a half-circle in the metal retainer/spring assembly.

Arthur Hollingsworth  created a video on how to perform this mod - You can view it here https://youtu.be/53VKmO8mqTc?t=1172



Steps

  • Locate 6 solder pads on the circuit board near the LCD display light
  • Remove the solder from the 6 pad connections
  • Remove the tuning control from the board
    Copyright Arthur Hollingsworth
  • Gently pry up the 4 metal tabs on the back of the tuning control with a small, flat bade screwdriver. Use a pair of needle nose pliers to remove any bends
    Copyright Arthur Hollingsworth
  • Gently separate the metal case and plastic control housing
    Copyright Arthur Hollingsworth
  • Remove the copper section from the 4 plastic retaining posts
    Copyright Arthur Hollingsworth
  • Using needle nose pliers, gently flatten the notch that sticks up on one side of the ring
    Copyright Arthur Hollingsworth
  • Reassemble the tuning knob in reverse order noting correct orientation (note the "detent" is now removed, but is shown here for reassembly reasons)
  • After the control has been put back together gently flatten the 4 tabs back into place using the needle nose pliers
  • Resolder the control into place on the PCB
  • Check your work and power up the radio
  • You should now be able to tune much easier now


73,
Jesse W9JES

Radio Shack DX-398 / Sangean ATS-909 Mods Part 2 - LED Replacement

This is one of the easiest mods you can do to a 909. Replace those dim, lime green LEDs with white ones!

All you need to do is desolder the old ones and replace them. Be sure to note polarity as seen on the PCB.






73,
Jesse W9JES

Radio Shack DX-398 / Sangean ATS-909 Mods Part 1 - Disable Mute


This radio design was sold under several brands including Radio Shack and Sangean. Radio Shack's model DX-398 and Sangean ATS-909.


Disable muting while tuning aka "chuffing"


This radio has a similar design to the ATS-818 where the PLL muting circuit is processed by the controller chip.


Steps


  • Disassemble the radio
  • Locate  CNT2
  • Find the Black Wire connected to PIN 10 and gently pry out with a small screwdriver
  • Use some heat shrink tubing and cover up the exposed pin and tuck neatly behind radio
  • Reassemble radio and enjoy!

Sunday, March 29, 2020

What do I look for in a shortwave radio?

A common question that I've been asked on my blog. What are some features that you find very important in a shortwave radio?



My listening preferences include talk radio, news, music, digital transmissions, and ham radio voice/data. Each person has different tastes when it comes to shortwave radios and I will try to generalize my list of must haves. but know there is some bias in my opinion. I am also interested in hearing about your opinions in the comments!

Must Have Features:
  • Physical Attributes
    • Sturdy, tactile feedback on the controls
    • Feels durable, not flexible
    • Ergonomics designed for frequent operation
    • Direct entry keypad
    • Rotary tuning knob
    • Tuning in 1KHz steps
    • RF attenuator (local/DX)
  • Frequency Coverage
    • Can listen to all commercial broadcast bands and amateur radio bands up to 29 MHz
  • Audio
    • Clear and intelligible sound from internal speaker for talk and music
  • RF Selectivity
    • Ability to reduce interference from nearby stations +-5KHz
  • RF Sensitivity
    • Ability to pull in signals at 2% over the noise floor (this is subjective as some radios measure sensitivity in dBm or ┬ÁV)
    • Adequate built-in antenna(s) to receive weak signals
  •  Double conversion receiver stages
  • Single Sideband (BFO or true LSB/USB)
  • Station Memory Recall
    • Ability to store at least 10 frequencies for quick access

 Nice To Have Features:
  • Large, bright, clear, and readable digital display
  • Selective backlight on/off toggle
  • Dimmable backlight
  • RF Gain Control
  • Triple Conversion receiver stages
  • Reputable internal components including filters
  • Dual power sources (house power and battery)
  • Recharging circuit to charge user supplied batteries
  • Line out jack
  • External antenna input
  • Audio filters (bandwidth, notch,tone)
  • RF Sensitivity to pull in signals below noise floor
  • Built in DSP signal decoders (DRM, CW, RTTY)

Friday, March 6, 2020

Radio Update

I've been very fortunate to pick up a "blue label" Sangean ATS-505 and Radio Shack DX-398 / Sangean ATS-909 this week. Both radios are expected to be delivered next week.






The current "red label" ATS-505 that I own has a bad encoder. I bought a replacement online, but it needs to be modified to work with the radio. The DX-398 has a deteriorated magnet in the speaker (common problem). My initial plan is to use the speaker from the ATS-505 "red label" for the DX-398.

I don't know if I will eventually repair the "red label" ATS-505 or just use it for parts in the DX-398 since many of the components are the same.

The good news is that I will be able to provide more content to you including modifications, enhancements, and repair information! Stay tuned!


73,
Jesse W9JES