======================
                              !  STANDARD  C 558   !
                              ======================

On march 3rd, 1993, I bought the Standrad C558S dual band HT. The price was
7,600 Austrian Schilling (approx. 580 US $ including all taxes).
CTCSS is not included in the European version!!

General information
=======================

Body dimensions:        55*130*31 mm (with CBT151 battery tray)
Weight:                 355g         (incl. batteries and antenna)
RF output:              5W (high,12V) 2.5W (mid) 350mW (low)

Freq. range of S version: VHF 144 - 148 MHz
                          UHF 430 - 440 MHz

Expanding the frequency range of the C558S
===========================================

1) software expansion(RX):
        I) reset the unit
       II) push and hold FUNC and press 3 - V/M ENT - 3
           release FUNC and  press PTT

   now the unit will RX 100-199 MHz (PLL lock range 100-173 MHz) AM + FM
                        300-500 MHz (PLL lock range 342-471 MHz) FM
                        800-999 MHz (PLL lock range 823-990 MHz) FM

  with this modification the HT can _NOT_ be tuned to all frequencies in the
  900MHz and 350MHz band!!!
  TX remains 144-148, 430-440 MHz

  smallest freq.step:
                        144MHz.....5kHz
                        350MHz.....5kHz
                        440MHz.....5kHz
                        900MHz....10kHz

2)hardware expansion(RX):

        I) open the radio.....
       II) locate resistor R289. its the 0 Ohm resistor on the micro-processor-
           board, right of the connector for the sub-tone sql. unit.
      III) remove the resistor..... :-)
       IV) reset the unit

 RX/TX range remains the same as above, but now you can tune to ANY frequency
 in the 350 and 900 MHz band.

3) hardware modification (TX):

        I) open the unit.....
       II) remove the 'galactic' RF-shielding from the micro-processor board
      III) locate smd-diode Q221 (its the right one of the two smd-diodes)...
       IV) the type of this diode is  DA115. exchanche it with a DAN202U or
          just solder a normal diode(1N4148) from the left pin to the lower
          right pin of Q221:

       type DAN202U smd diode:

             -------
             |     |
             | -|<-|==
             ||    |
           ==|-    |
             ||    |
             | -|<-|==
             |     |
             -------

       type DA115 smd diode:

             -------
             |     |
             | -|<-|==
             ||    |
           ==|-    |
          |  |     |
          |  |     |==
          |  |     | |
          |  ------- |
          |          |
           ---|<-----

             1N4148


        V) reset the unit....

  the TX range will be: VHF:100-199MHz (PLL lock range 115-165 MHz :-(  )
                        UHF:400-500MHz (PLL lock range 400-482 MHz !!)

  no TX in the 350 and 900MHz band


Pro's and Con's of the C558
=============================

  + one of the smallest 2m/70cm HT
  + extremly sensitive and low noise receiver(even on 900MHz)
  + very low power consumption
  + up to 200 memories with a lot of different scan modes
  + good keyboard layout (except the 1750 Hz burst tone!)

 +- the rubber-duck antenna works very good in the ham-bands and 900MHz
    but does not work at all outside the 2m ham-band :-(

  - the worst case I have ever seen -- so don't drop the C558!!
    ( Radio-Shack's CB walkie talkies can't be worse )
  - some intermod. problems with high gain base-antennas
    ( but much better than the yaesu FT530!! )
  - small LC-Display
  - no backlit keys
  - the mic/speaker cap ... you have to see THIS yourself :-(
  - press PTT and CALL/PL key to activete 1750Hz tone...



If you know some other information about the C558 please tell me....

73/Harald, OE5LEN.....

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                                            |
  packet:     oe5len @ oe5xem.aut.eu        |           A U S T R I A
  internet:   oe5len @ edvz.uni-linz.ac.at  |  high mountains - no kangaroos
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