AudioControl's Mod's

All information on this and proceeding pages is intended for educational purpose's only. So if you must use this information do so at YOUR OWN RISK!!

Galaxy 99

  1. Remove the case and find the small circuit board (EOT004410Z) connected to the left side of the radio as viewed from the component side of the main chassis.
  2. Find the wire that is connected to this circuit board remove this wire.
  3. Remove the small screw that holds the small board on to the chassis. Under this board you will find a 7 pin plug that is not connected to anything. Insert this plug into the empty socket on the small circuit board. Replace screw back into the small board and close case.

Expanding the MB8719

(Models include: Uniden Grant/Madison, Cobra 148/2000 GTL etc...)

To get coverage from 27.455 - 28.045,

  1. find the MB8719 PLL, then locate pins 10,11and 12. Cut the trace going to these pins. Locate a ground (chassis or track) .Using a DPDT Center off switch, connect the switch to pins 10,11,12(IC side of the cut) on the MB8719 PLL.This Mod will give you the normal channels 1-40 in the center position. In the Down position 27.605 - 28.045, In the up position 27.455 - 27.605( on channels 2 -14).
  2. Further expansion can be done by replacing the loop mixer crystal, giving you a new set of 40 channels per crystal

Emperor 5010

  1. Remove the four screws holding the bottom cover in place. Lift the bottom cover enough to clear the case and slide it to the side while being careful not to detach the speaker wires. You should now see the PLL/CPU board at the front of the radio.
  2. With the front of the radio facing you, locate R539 and R540 at the lower right corner of the large chip(HD614081), R539/R540 are side by side and very small. Remove R539 and R540. You now will get 26.500Mhz to 27.999Mhz plus the 'FCC' band in nine bands.

MC145106 PLL

This PLL includes the following models...

For Export Models eg. This PLL is getting used in a lot of newer radio's. It often has a pair of MC14008 binary adders to extend the amount of channels available.The PLL uses 9 bit binary programming with internal pull-down resistors. Modifications are possible by changing the binary programming... or changing the mixing crystal.


This chip can be found in many radios. This mod might also work on the SSB units.
G.E. 3-5804D,3-5811B,3-5812A,3-5813B,3-5819A
Midland 76-858,76-863,76-886,77-830,77-838,77-849,77-857,77-8 82,77-888,77-899,77-955,77-963
And just about anything with a PLL 02A chip in it. The 23-channel radios will give different channels.

This will give you 27.425 to 27.705 Mhz on channels 12 - 38.

This will give you 26.435 to 26.7455 Mhz on channels 10 - 38 . When the switch is DOWN. This will give you 26.755 to 27.055 Mhz on channels

Ranger RCI 2950

The only difference between the old and new versions of the RCI2950 is the new CPU board. They require slightly different modifications. Old Version The old version of this radio can be expanded from 26 Mhz to 32 Mhz. Although the use of the 30 -32 Mhz range may need realignment.

  1. First find the PC board with the jumpers on (behind the front panel).Then find 'J2',there is a jumper on pins P3 and P4.If this is jumper is removed you will get coverage from 26 Mhz to 29.7 Mhz.
  2. If this jumper is then place on P1 and P2 coverage will be from 26 Mhz to 32 Mhz(re tuning may be needed to operate in 30-32 Mhz range).
New Version As the CPU board has changed the modification is different. On the CPU board there is only one jumper with two positions available. In one position it covers 28 Mhz to 30 Mhz, In the other it covers 26 Mhz to 30 Mhz. But if you jump all three pins together you'll get 26 Mhz to 30 Mhz.

Uniden HR2510

This radio can be expanded to cover 26-30 Mhz without the need to realign!

  1. Find IC315(UC1201A,UC1170,UC1250a etc) on the synthesizer board PB121BB.Then locate pins 34 and 35 on that chip, these pins are grounded on the HR2510. But on the European models like the President Lincon they are tied high(+5 Vdc). Therefore to get the extended coverage needed these pins should be tied high.This can be done in the following way.
  2. On the solder side of the synth board pins 34 & 35 are grounded by the same trace. With a razor blade cut this ground trace.
  3. Now find resistor pack RR301.The left pin of this pack is unused and goes to a solder pad. Now connect a small jumper wire between this solder pad and pins 34 & 35 on IC315. Now you should get coverage from 26.000 Mhz to 29.990

Cherokee AH-100

To expand this radio to 400 channels, do the following..

  1. Remove the back cover. Find the small circuit board that has the PTT and UP/DOWN switches. On the reverse side of this PCB look for 3 solder islands that end on the outside edge of the board.
  2. Solder a bridge across all three islands. Re-assemble radio.
  3. Then do the following... If the radio has been used before you will need to remove the battery and with the power switch ON short out the supply terminals for about a day. This will cause the processor to clear it's self.
  4. Make sure the power switch is on hold down the CH9 button and slide the battery pack back on. Now you should be able to hear the receiver but no display, release the CH9 button and the display should reappear. Now using the CH9 button you should be able to select 10 bands of 40 channels (A thru J). Now whenever you power up the radio with the CH9 button held down you'll get 400 channels..If you do not hold the CH9 button down you will get the standard 40 channels.

Midland 79-290

  1. To set radio foe 240 channel mode press and hold "DW" and "9" then turn radio on.
  2. Select bands by using the "19" button.
  3. To set radio for 28Mhz to 29.7 Mhz press and hold "LCR" and "eMIC"e then turn radio on. To switch back to 40 channel mode repeat process.

Galaxy DX 2527

Remove the top cover. Just above the PLL you will find a jumper block. There is only one jumper on this block..Move the jumper from bottom left position to top right position.






Sign Guestbook

View Guestbook

You are visitor#

Last update 11/21/99

1998 AudioControl

CB Radio Operators Web Ring Home Next Great CB Radio Site This CB Radio Operators Web Ring
site is owned by

Search The Web Ring

Want to join the
CB Radio Operators Web Ring?

[Skip Prev][Prev][Next][Skip Next][Random/a>][Next 5][List Sites]

This page hosted by GeoCities Get your own Free Home Page

Hosting by WebRing.