Sunday, November 16, 2014

ALS-1300 repair : +15 V Power supply, Protection circuit


Symptoms:
 1. +12 V Power supply is out
   + 12 V of PS module #1 is not working!
  Other voltages look okay.

 - Trying with an external variable voltage/current power supply as shown in the picture below.

2. Both PA and SWR LED are on at the Operate position. No PTT engagement.

  A. At Standby position, consume 630mA
  B. At Operate position, it draws 920 mA (for one relay and two LEDs?) and PTT is not working.







Look up the schematics provided by Ameritron.
Control circuits has to be checked, especially those Diodes and CD4042 which drive those LED and protection logic.

Finally, I opened the amp cover. What a SCREWS!!

D1, D2, D3, D4, D5, D6, D7  read okay to my DMM

Touched the CD4042 to remove,, Yeap!!, the 4042 is hot!





Now I ordered a 15V 2A SMPS and a few CD4042BE from eleparts. 
The T/R relays are already there at OM's home.

 1. Attach and wire +15V supply.  Set voltage at +14V
 2. Replace CD4042
 3. Change T/R relays
 4. A LOT OF SCREWS!!!


Monday, October 06, 2014

SDx - Software Defined Something/Anything


I call it SDx - Software defined someting/anything!

I call it SDx - Software defined someting!
I call it SDx - Software defined anything!
I call it SDx - Software defined whatever~


How about Software-defined marketplace or software-defined pub?

SDR - Software defined radio
SDS - Software defined storage
SDX - Software defined exchange
SDDC - Software defined data center
SDM - Software defined market....................


Tuesday, March 18, 2014

TL-922 links



http://www.2333.net/~ji3kdh/weblog/archives/2012/04/tl-922_18.html

http://search.nifty.com/websearch/search?cflg=%E6%A4%9C%E7%B4%A2&select=79&q=tl-922&ck=&ss=ccrank


http://jf3dri.tea-nifty.com/blog/tl922/index.html