8727 Restoration & Repairs

 

This model radio is basically a much upgraded 7727 in theory with the same features

in a new layout making it easy to service and use. It also comes in a Local and remote

models for either base or vehicle uses. Accessory hardware compatible with the 85XX

range of radio's. See Museum section for more details.

 

Specifications:

Frequency Range  2-16MHz

Channel Capacity  10 (crystal)

Modes  USB (J3E), LSB Optional

Output Power  100Watts

impedance  50 Ohms

 

Options:

Option AS   Antenna Selector

Option PL   Extension Loudspeaker

Option PS   External Selcall

Option E     Emergency Call (RFDS)

Option PH  6.5mm Headphone socket (Local Only)

Option L     LSB Optional

Option BB  2 frequency simplex for upto 2 channels

Clarifier Optional (CAN, CAW, CBN)

remote head 8730

Suitable power supplies 7113-B  or  8540/B

 

Serial Numbers Vs Operating Frequency's:

Serial Number A1234 has a PA that operates from 2-18MHz

Serial Number B1234 has a PA that operates from 2-24MHz

Again these PA's are the same used in 85XX series radio's and are interchangeable.

 

Recrystaling Adding a Channel Kit:

The most common problem with this series of radio is recrystaling or adding a channel kit.

Now for the problem, the coils used in either the early 6801, 6924, 7727 are to some degree

compatible, the 8727 has different value internal components making it difficult unless you have

a scrapped radio in order to take coils from. Modification of the coils should only be undertaken

by someone with great electronic knowledge and dexterity, i have destroyed more coils then i

care to mention....!     SO its all at your risk.

Range     Models

6801

6924

7727

8727

2 to 10.6MHz

70031

70031

70031

70386

10.6 to 16MHz

70074

00000

70074

70387

                                 Coil Can Numbers

 

 

8727

7727

6801Mk2 & 6924Mk2

C

333

473

473

R

100

1k5

100

Coils for Standard 6801,6924,7727 are NOT compatible with Mk2 Radio's.

 

                                                Option BB 2 Frequency Simplex

 

                                Filter Selection

 

                                                               Option LSB

 

                                                    Option E  Emergency Call  (RFDS)

 

                                                              Option PS for external Selcall

 

                                       Option LF & Possible Talk Power Mod, PA module.

 

                         Closeup of added parts for channel 4, pretest before doing channel 5.

 

                                             Adding coil kits and associated parts. channel 4

 

 

                                                                           Adding channel 5

 

                                   Back of the channel board showing parts and links to be added.

 

Setting the frequency for channel 5, Now putting it this close to the correct frequency, it wont be this radio's

fault if everyone else sounds like donald duck on air. (off frequency).

 

                                                       Setting the frequency for channel 4.

 

                            Finished Radio cleaned ready to be sent back to its owner.