The AR7 Receiver Restoration Project

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About three years ago I purchased a WW2 AR7 receiver made by Kingsley Radio. It was full of rust and insects, and the panel was badly damaged. It was put away in a box awaiting a decision on its fate. I am pleased to say that it is up and running again after a tedious restoration (some would say rebuild) project.

This section will be updated again soon with the final photos of the receiver and it will also contain more details of the project and a little history of the Australian copy of the HRO, the AR7 receiver

From this

The old AR7 in the condition it was in when purchased.

The underside was reasonably clean but most of the resistors were original and very doubtful

The front panel was very damaged, knobs missing and note the thick rust in the coil receptacle area

The unit was stripped down to the last piece of metal and all the metal was cadmium plated and passivated. The braid was replaced with new but since the plating would not accept solder, solder lugs were used for all chassis connections. The advantage is that major components can now be replaced if necessary without too much trouble.

The valve sockets were replaced with the brown molded type from Command receivers of the same vintage. The AR7 sockets were quite useless. A major problem was the contact strip which makes connection with the HRO style plug in coils. It was broken into three pieces. It was glued together, reinforced with a strip of fiber-glass and all contacts re-riveted  back on.

 To this

The front panel, being springy stainless steel was quite impossible to straighten. It was replaced with a cleaner one from another AR7. This one had been painted grey, and I ask, for what reason? People do strange things. The paint was removed with paint stripper and there was a nice panel underneath.

Yes, there are a few wires to tidy up. I have had to turn up a valve shield on the lathe for one of the 6U7G's. I am looking for a set of original valve shields if anybody can spare them. I need 7 shields in all.

The underside of the receiver as it now is. It still resembles an AR7 as I went to great lengths to get as many components as close to their original position as possible. Most of the small components have been replaced with new ones. Even the old wiring loom has been replaced with a new one made from PVC wire. There is still more work to be done but the unit has been fired up and is working fine. A bit of the wiring still has to be tidied up and a phone socket added. It will be used mainly for AM contacts in the VK2BA station.