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Coronado 550
2/24/2004 1:37:27 PMRick
I have recently become the owner of a Coronado 550 battery powered radio due to a death in the family. Knowing nothing about how to restore anything like this, can anyone point me in the direction of how to get this radio working?

Many Thanks

2/26/2004 10:22:20 AMPoston Drake
Hi Rick,
You can find a schematic and parts list for your radio here on NostalgiaAir. From the "Resources" section, click on "Gamble-Skogmo, Inc.", then scroll down the list of model numbers and click on "550".

Before you can power up and test your radio, you will need a power supply as the batteries are no longer available. Your radio uses 2 volts for the A+ filament supply and 90 volts for the B+ plate supply. Temporarily you can rig up batteries by using several 1.5 volt D cells in parallel for the A+ filament supply circuit and ten 9 volt transistor batteries in series for the 90v B+ plate supply circuit. Be sure and make the proper battery connections as shown in the schematic, since if you apply the 90v to the A+ filament circuit you will burn out all your tube filaments instantly. For long-term service you may want to build a power supply, several designs are available online. Battery eliminator kits are also sold by Antique Electronics Supply www.tubesandmore.com

You may find it necessary to replace several or all of the paper capacitors in your radio. Here is a website which explains this, and gives other valuable information for those new to radio repair:
http://antiqueradio.org/begin.htm

Poston


:I have recently become the owner of a Coronado 550 battery powered radio due to a death in the family. Knowing nothing about how to restore anything like this, can anyone point me in the direction of how to get this radio working?
:
:Many Thanks

11/29/2005 6:44:25 AMLenny Prince
:I have recently become the owner of a Coronado 550 battery powered radio due to a death in the family. Knowing nothing about how to restore anything like this, can anyone point me in the direction of how to get this radio working?
:
:Many Thanks
11/29/2005 8:44:25 AMRadiodoc
::I have recently become the owner of a Coronado 550 battery powered radio due to a death in the family. Knowing nothing about how to restore anything like this, can anyone point me in the direction of how to get this radio working?
::
::Many Thanks

Lenny,

The schematic is located on this site at http://www.nostalgiaair.org/PagesByModel/067/M0007067.pdf.

Radiodoc



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