Hardware Hacking

Conversion to lower sideband.

Remove power, antenna, and microphone.
Remove upper and lower covers.
Remove PLL board.
Locate L12. Beside L12 is a 12 pf capacitor, replace this with a 47 pf.
Adjust L12 for best clarification on known signal source.
Reassemble radio.
You now have lower sideband and cw.

Remove bottom cover. With the radio upside down and display facing you remove
the synthesizer board with the four screws, this is near the front of the radio.

This gives access to the small board underneath with the surface mount
components on it. Locate the processor chip IC401 (UC-1208).Locate pins 28 and
29 which are on the right hand side of the chip and are 4th and 5th from the
top. Note they are bridged with solder.

CAREFULLY cut the copper track NEXT to the pins. DO NOT attempt to unsolder the
two pins form the board. Use a GROUNDED soldering iron. Locate the two rows
of connector pins above the chip.

On the bottom row locate the last pin on the right. Verify with a VOM that this
pin has + five volts. Solder a 10k (1/4 w) resistor between this pin and pins
28 and 29 on IC401.The synthesizer will now tune from 26.00 Mhz to 30 Mhz.

——————————————————————————-

*Simple RF Wattage Enhancement to 35 Watts

With the radio in the same position as before, locate VR5 in the top
left hand corner. This is the RF high power preset.

Lift and bend the wiper so that is is permanently disconnected form the track.
Solder a 47k resistor (1/4 watt) between the wiper and the left hand side of
the track.

This should increase the RF power output to around 35 watts but you will now
not be able to trim the power output. The Low power trim will function as
before.
——————-

Enhancement of Microphone Frequency Response

1) To increase average depth of modulation
– — ————– —– — ———-
Remove top cover of the radio and with the display facing you and the radio
upright locate IC3 (MJM45585) near the bottom right hand corner of the main
large board.

Just to the right of this IC locate c75 (56 pf) and remove it. This will
increase the gain of the microphone Preamp considerably but without
overmodulation. If you find the compression excessive(i.e. background noise)
open the microphone and insert a 470 ohm resistor between the hot side of the
mic insert and the input (white lead).

This will reduce the gain somewhat but will still give you much increased
“talk power” (percy’s words, not mine. Adam).

2) To increase audio response in the high mids
– — ——– —– ——– — — —- —-

This simple mod will recrease the audio response in TX in the 2 to 2.7 khz
region giving higher articulation and move intelligibility under weak signal
conditions.

Locate IC3 as before on the large main board and the radio positioned as before.

Locate a 5.6k and a 4.7k resistor just below IC3.
Solder a 0.015 mf (16v) capacitor between the left side of the 4.7k to the
right side of the 5.6k resistor.

These two mods work together to give improved readability on SSB under DX
conditions.

Keyboard

With the radio on.
1. Press “F” and “0″ to enter main menu. Press “14623″ consecutively until you here the confirmation beep.
Turn off the receiver and turn it back on. Now the receive modification is done.
2. Press “F” and “0″ to enter main menu. Press “1462311289″consecutively until you here the confirmation beep.
Turn off the receiver and turn it back on. Now the transmit modification is done.

Hardware (CAUTION: It voids the warranty.)

1. Open the radio and remove Q220 from the keyboard.
Turn on the radio by pressing “F”, “LAMP” and “5″.
2. Open the radio and remove Q220 and Q221 from the keyboard.
Turn on the radio by pressing “F”, “LAMP” and “5″.

If you have version 1.00 + 1.10 (Radio Shack’s HTX-204 included):

Keyboard 1: RX 100-200, 330-500, 830-868, and 896-999.995 MHz; TX same
Keyboard 2: TX 100-200, 400-500 MHz; RX same

Hardware 1: RX 100-199.995, 330-499.995, 830-868, 896-999.995 MHz, TX same
Hardware 2: TX 100-199.995, 400-499.995 MHz; RX same

If you have version 1.20:

Keyboard 1: RX 100-200, 330-500, and 896-1000 MHz; TX same
Keyboard 2: TX 142.5-149.5 MHz; RX same

Hardware 1: TX 138-174, 430-470 MHz; RX 130-174, 350-470, 869-999.995 MHz.
Hardware 2: TX 100-200, 400-500; RX 100-199.995, 330-499.995, 896-999.995 MHz.

If you have version 1.30:

Not available at present.

Cellular Bands Information for ADI-600

Mobile Cellular (823.9275 - 851.0000 MHz)
- Unable to receive
Portable Cellular(868.9375 - 896.1125 MHz)
- 913.0375 - 940.2125 MHz (FM Mode)
- Set frequency step to 30 kHz after you find one frequency that is used for the cellular in your area. This will work perfect.

Mod: Expands TX from 143-149mhz to 136-174mhz

Tools Required: Phillips Screwdriver, Mini screwdriver, Soldering Iron (Fine
tip) , NeedleNose Pliers

Process:

1. Remove Screws on bottom and top
2. Take the Bottom and Top off the Radio
3. Unplug Speaker from top of the radio and remove the dials from the face plate
4. Unscrew the screws on the top and bottom of the face plate.
5. CAREFULLY: remove the face plate from the radio
6. Remove the bolts and washers (little rings) from the dials (countersunk into the dials).
7. CAREFULLY: remove the LCD and plastic around it by pulling gentle and wiggling it a little being careful not to bend the LCD pins.
8. Remove the screws holding down the PCB from the cases
9. CAREFULLY: (Plug in type PCB) remove the PCB from the radio and place the VFO tuning dial face down and to your left.
10. There will be two blue jumper mounts on the PCB. Remove the 1 closest to the 2 black raised chips that are closest to the VFO tuning dial (this jumper should be near the middle of the board) The other jumper makes
the transmitter do 143-144 (military) and it is near the side.
11. Put all the parts back together and blamo you have 136-174mhz RX/TX

this mod is for the new dual band HT from radioshack cat#19-1106

out of the box the radio will go from 144-148 rx/tx and 438-450 rx/tx

the mod will rx and tx from 136-174 and 420-470

1. remove screws from back cover and battery compartment
2. remove nuts on volume and antenna jaack
3. unsolder speaker connections
4. carefully remove entire circuitry from shell
5. the smaller circuit board will un plug from main board
6. towards the middle top of the large circuit board their is a black square processor chip. to the left corner their are 2 solder pad jumpers that are facing vertical in comparison with the board. to extend rx
remove bridge closest to right side. (the left jumper will only allow 144-146 and 430-440 tx/rxonly)
7. to exend transmit unsolder the other pad that is horizontal in comparison to main board. (if MARS/CAP is wanted just remove the horizontal jumper and leave other alone.140-149rx/tx)
8.reassemble radio
9. reset radio by pressing (MF) and (6) key while powering on.