Dawn
Member
As I've written before, I've been slowly doing restorations for folks that want to pay for the work done professionally. Most of these are some of the older luxury bases. While E-bay is a great source for radios to cannibalize for parts, some things just aren't easy to replace. Among them are the mechanical clocks that often have burnt out synchronous motors or serious slippage problems. That seems to be a common problem with the standard movements used in the 70's I believe made by Sankyo. Sometimes the slippage can be remedied by a drop of crazy glue on the gear, other times, from age, there's missing teeth. I've had some that came to life after cleaning gummed up bearing points with CRC's electro clean and relubing. Many now have faded or yellowed and the biggest mistake you can make is try to use a harsh cleaner on the numbers. The print is easily damaged. Donor radios often have the same problems after 35-40 years. What I've found to be a great upgrade is E-bay has numerous Asian vendors selling two versions of a 4 digit digital clock that can be mounted on a piece of perforated circuit board painted black on the non foil/pad side and then the board mounted on the 4 screws. They're available in two sizes. The .36" versions will fit very nicely in the window type openings. The .56 larger ones will fit over the slot opening type bezels if you bend the apertures in or remove them and use the board method. The two holes can be put to use as there are two switches on the boards. One hole is about 10MM and the other about 5MM. RS sells those large, red push buttons with a momentary contact for the larger hole and the smaller can take a spdt momentary toggle switch. Both are paralleled to the board switches for function and set. These are only 24hr clocks, not capable of 12 hr and can also show voltage and temperature in C only. They need no time base and are battery backed up for about $7 shipped. There are some stateside and Canadian vendors selling them for about double if you don't want to wait. Most are red, but there's also a green sold by some..haven't seen a blue yet. Point is, they are ideal to replace the clock in older radios and update it too. The owners have been quite happy with them despite the 24 hr limitation. In some radios that didn't have a clock, but have a space you can either cut with a hot knife or place under the transparent front panel. I did one of those Sears SSB bases with the slide controls using the .36 size under the status LED's that way.
Mics too have been a problem. Many have open coils on the cartridges from corrosion at the two solder pads that usually are totally corroded. The baffles are also so full of dried residue from spit and dust that a run in an ultrasonic cleaner can make a big difference or perhaps just washing them with a soap and water with some ammonia added. There are replacement cartridges available from workman, but hardly worth it or of the same quality. I've found taking a piece of closed cell hard polyurethane foam that you can buy at a fabric shop in a sheet and cutting a circular piece to fit the mic and punch a hole in the center and mount a radio shack electret mic is vastly better and an upgrade. Minimally you just need to get about 5-8 volts to the cartridge through a resistor of about 8.2k which isn't critical and decouple with a 1 uf electrolytic for the output. It's a good idea to put a .001 cap across it for RF bypassing as well. Changing the 1uf cap to something smaller will roll of the lower end you really don't need as the response of these mics is way lower then a dynamic. This is a cheap way of really upping the performance of an old or dead mic. Most mic connectors either have 5-8volts on one of the pins or in the case of DIN plugs it can be added and the wire is already there in the mic. Radio Shack compatible mic pinouts often have a hidden 12V on pin 2 of the radio that's there but not documented. Hitachi did this in a lot of radios by RS and Sears. The amp and in some cases compressor of the mics like the +3 are better off replaced. Lou Franklin sells a hell of a little board that offers both for about 30 bucks or you can copy the circuit. This totally blows away any Turner compression/amp and will allow you to match the mic to just about any radio if you want to go that far. If you want to narrow the audio for sideband and more punch in the voice region, add a .047uf cap with a 10K pot across it in series with the hot side of the mic and adjust it to your voice for a punchy response. I've done some old sharkfins this way and a yaesu mic with excellent results the owners have been really happy with.
Most of these have dead bulbs and in some cases, the bulbs running hot have warped plastic parts. Plenty of vendors are selling bright white or blue LED's in a 5mm size with a series resistor as a replacement that will fit in a grommet and replace the bulb perfectly.
Plenty more things, but I figured these might give some you guys a good idea to work with. If there's any interest, I'll post some links.
Mics too have been a problem. Many have open coils on the cartridges from corrosion at the two solder pads that usually are totally corroded. The baffles are also so full of dried residue from spit and dust that a run in an ultrasonic cleaner can make a big difference or perhaps just washing them with a soap and water with some ammonia added. There are replacement cartridges available from workman, but hardly worth it or of the same quality. I've found taking a piece of closed cell hard polyurethane foam that you can buy at a fabric shop in a sheet and cutting a circular piece to fit the mic and punch a hole in the center and mount a radio shack electret mic is vastly better and an upgrade. Minimally you just need to get about 5-8 volts to the cartridge through a resistor of about 8.2k which isn't critical and decouple with a 1 uf electrolytic for the output. It's a good idea to put a .001 cap across it for RF bypassing as well. Changing the 1uf cap to something smaller will roll of the lower end you really don't need as the response of these mics is way lower then a dynamic. This is a cheap way of really upping the performance of an old or dead mic. Most mic connectors either have 5-8volts on one of the pins or in the case of DIN plugs it can be added and the wire is already there in the mic. Radio Shack compatible mic pinouts often have a hidden 12V on pin 2 of the radio that's there but not documented. Hitachi did this in a lot of radios by RS and Sears. The amp and in some cases compressor of the mics like the +3 are better off replaced. Lou Franklin sells a hell of a little board that offers both for about 30 bucks or you can copy the circuit. This totally blows away any Turner compression/amp and will allow you to match the mic to just about any radio if you want to go that far. If you want to narrow the audio for sideband and more punch in the voice region, add a .047uf cap with a 10K pot across it in series with the hot side of the mic and adjust it to your voice for a punchy response. I've done some old sharkfins this way and a yaesu mic with excellent results the owners have been really happy with.
Most of these have dead bulbs and in some cases, the bulbs running hot have warped plastic parts. Plenty of vendors are selling bright white or blue LED's in a 5mm size with a series resistor as a replacement that will fit in a grommet and replace the bulb perfectly.
Plenty more things, but I figured these might give some you guys a good idea to work with. If there's any interest, I'll post some links.