Panasonic RF-2200 restoration adventures - Final

This is the last post (here the previous one) of a series about the restoration of my Panasonic RF-2200 vintage receiver. This is about the final cleanup of the radio. In one of posts I spoke about restoring proper behaviour of switches and potentiometers by using the renowned DeoxIT products from CAIG Labs. While these products proven to be very effective in my case, however I suspected I had used a bit too much of them for each device. So before re-mounting the case of the radio, I wanted to try to remove out any excess of DeoxIT from inside switches and potentiometers, by spraying a lot of compressed air into each device. Well, the amount of DeoxIT that came out from potentiometers were really in excess! It spread out over the main circuit board - without causing any damage, luckily - and I had to carefully remove it with compressed air, paper towel and some cotton swabs.
My recommendation is to use only the strictly necessary amount of DeoxIT (or similar product), especially if it is in the liquid form (the spray form usually contains a reduced grade of product, which easily evaporates together with solvents).
I already had cleaned up the front panel, back panel and the knobs in a soapy bath of warm water (see pictures below), using a soft brush for the panels and a toothbrush for the knobs.

Now I had only to re-mount the radio and proceed with renewing the black plastic of the case. I started with trying the Novus 3 Heavy Scratch Remover, but it did not a great job. I have found it too thick and a bit waxy, difficult to remove when it permeates the small wrinkles and scratches on the black case, causing it to look a bit milky and opaque, not that good really.
Then I tried to repair to my error with a normal, typical spray polisher for car dashboards. Boys, it did it! Faster, easier, cheaper and very effective: ideal for my needs. The results are in pictures below. Far from perfect, but good enough in my view.

That's all folks! I hope you have enjoyed your reading (thank you for that!) and may be you have found something useful for your own restoration project. These beatiful old ladies are well worth the effort.

Panasonic RF-2200 restoration adventures - Part 3

This post follows Part 2 on the same subject. As anticipated, I proceeded in the restoration project of my Panasonic DR-22 (also named the RF-2200BS) with trying to clean-up contacts of front-panel switches and potentiometers.

For this purpose I bought some products: a spray "dust remover" (compressed air) and a couple of well-known products from CAIG Laboratories: the DeoxIT D100 for switches and the DeoxIT Fader for potentiometes. Here below a picture of the toolkit, ready for use:

First step was to try to remove as much dust as possible from inside the case, the switches, the potentiometers and the tuning variable capacitor. Using a bottle of spray compressed air was quite appropriate for this operation, as illustrated by pictures below:

Next step was to use DeoxIT D100L cleaner to restore proper behaviour of contacts in front-panel switches. CAIG guidelines recommed to always wipe off excess of their products. However, wiping off excess is sometimes not possible, especially if the cleaner is applied into a semi-sealed part, like in my case. If this happens, CAIG recommend to just apply a small amount of their product into the part to be cleaned. Here is where the "small squeeze tube" type of applicator helps (compared to the more common spray type), as it allows providing small drops to the target device.

Final step was to apply the CAIG Fader F100L to the potentiometers, to restore and lubricate their internal contacts. Here again, the small squeeze tube applicator proven to be perfectly suitable for my needs:

Just after a single application of DeoxIT, I noticed a significant improvement in contact reliability of switches and in noise of potentiometers. Nevertheless, the 125 kHz marker switch will require a second application of DeoxIT, as it still works not perfect. I plan a second round for it just before re-assembling the unit in its case. Stay tuned for more RF-2200 restoration adventures.

Panasonic RF-2200 restoration adventures - Part 2

Among first steps of almost any radio restoration projects is to dismantle the unit, both to ease deeper cleaning and to gain access to the circuit for visual inspection and - later on - for realignment and calibration. So I did. Attached below please find a collection of pictures showing the internals of my new old Panasonic DR-22 (refer to Part 1 for some more background on this story).

The solder side of the main board with the front panel controls exposed

The nice old-style mechanics of the tuning scale

The component side of main board with the tuning capacitor well exposed

Luckily, it seems that the unit does not have suffered from any major fault or repair in its past life. Internally it appeared fairly clean and in good order. After having removed the five self-evident screws on the back panel (only one of them is "hidden" inside the battery compartment) and the knobs on the front panel (all but the main tuning knob), both panels can be easily separated from the main circuit board so exposing that nice piece of vintage electronics.
It is very good for us experimenters that the whip antenna, the battery compartment and the loudspeaker can be easily disconnected from the main board without having to use a soldering iron. The radio itself can still stand up without the front and back panels and it can be very easily serviced this way, with a minimum risk of causing mechanical damages. Well done, old Panasonic designers!

The back panel dismounted with connections for antenna and batteries

Unfortunately while separating the front panel from the main board, a piece of plastic detached from around the signal meter (circled in yellow in image below). The other small rectangular piece of black gummy plastic silently dropped from inside the radio while detaching the back panel. I couldn't find out where it came from. I hope to discover its original placement while rebuilding the set.
Now I'm waiting for a stick of the renowned CAIG DeoxIT D100L conctact cleaner and another stick of DeoxIT Fader F5 for potentiometers. After having recovered a good behaviour of switches and pots I will proceed with a realignment. Stay tuned for more RF-2200 restoration adventures!

The rear of the front panel with the loudspeaker

The timestamp above says (I suppose) December 24, 1977

The venerable front panel dismounted and ready for a careful cleaning