Radio - Static Troubleshooting
88peugeot05BULLETIN NO. 283
DATE: July, 1988
SUBJECT: INSUFFICIENT AM SIGNAL STRENGTH AND/OR EXCESSIVE STATIC IN FRINGE AREAS
PROBLEM:
A 120-130 pf condenser is installed in series with the center conductor of the coaxial cable (P/N 6514.31) that connects the rear antenna to the radio. This condenser slightly reduces the AM signal at the radio.
This condenser may be removed for a further improvement in AM radio performance, but it should not be removed without first having performed the diagnosis procedures outlined in this bulletin.
Removal of the 120-130 pf condenser will result in a 10-20% increase in "listenable" AM stations, a slight reduction in static, and a slightly noticeable increase in station clarity on 50% of AM stations.
FM reception will not change or be improved with this modification.
DIAGNOSIS:
Industry specifications for radios are such that a variance in tuner performance can exist; however, most poor radio reception complaints are antenna related and can be diagnosed as follows:
1. Tune to a very weak AM station, one with either slight background static or one with a weaker second radio station noticeable in the background.
2. Disconnect the coaxial cable from the power antenna and install a manual antenna:
If station noticeably improves ---> install new antenna.
If no improvement ---> go to step #3.
3. Bypass the antenna-to-radio coaxial cable with a new known quality cable routed outside of the vehicle. The continuity of the coaxial center conductor cannot be checked as the presence of a 120-130 pf condenser in series with the center conductor will register as an open circuit (infinite ohms) if checked with an ohmmeter.
If station noticeably improves ---> replace coaxial cable.
If no improvement ---> go to step #4.
4. Set a known quality radio on another vehicle to the same station and observe signal strength
If station very noticeably improves ---> replace radio.
If no improvement ---> go to step #5.
5a. Remove radio for access to antenna-to-radio coaxial cable (P/N 6514.31).
b. Place fender cover over console and rug to prevent dropped solder from making burn marks on interior.
c. Unplug coaxial cable from radio and with snips, cut off just behind male connector:
d. With a razor blade, carefully cut and strip off 50 mm of outside rubber insulation (A), 30 mm of center conduction insulation (B), and cut and pull back the braided shield wire (C) 10 mm as shown below:
e. Purchase a male antenna plug (Radio Shack "motorola type plug" #274-711 or equivalent).
f. Using rosin-core solder, tin 3 spots as shown circled below:
g. Slide the antenna plug over the coaxial cable, aligning it as shown by the dotted lines above. HINT: Look in direction shown by arrow and guide center conductor into center of antenna plug. If it does not stick through, it is bent; try again.
h. Place the coaxial cable with antenna plug installed in vise grips with just enough pressure to hold it in place:
i. Solder the center conductor (G) to the antenna plug at (F). While applying slight pressure with pliers at the locations shown by the arrows above, solder the braided shield wire at (H).
j. Snip off the excess center conductor at (F).
k. File off any excess solder at (F) which would prevent the plug from being inserted into the radio antenna cable or receptacle.
l. Insert coaxial cable into radio and reinstall radio.
m. After this modification, check reception to be sure antenna plug is soldered properly. If necessary, check continuity:
a. < 1.5 ohms between both ends of center lead (this specification only applies to modified coaxial cable)
b. < 1.0 ohm between both ends of shielded (braided) wire
c. infinity ohms between center lead and shielded wire
WARRANTY INFORMATION: