Over the next month or so I plan on tackling the restoration of this AGE Bandmaster.

This receiver was made by AWA for the Australian General Electric Company in 1935 and contains the same chassis as the R29 Radiolette. At this time all versions of this radio in timber cabinets were badge-engineered AGE with AWA-badged sets shifting from timber to bakelite, though both timber and bakelite receivers enjoyed the 'Empire State' shape that lead to the eventual design of the AWA Building at 47 York Street, Sydney - all of this being inspired by the art deco style of the Empire State Building in New York, USA.

This set currently works however the sound is dreadfully tinny and a number of modifications have been made that detract from the set's heritage value and will require reverse-engineering. The first is that the output valve has been changed from a 42 to a 6V6G. The person who did this modification obviously did it some years ago when heritage would have been the last thing that the owner at the time would have reasonably been asked to consider. Being in a timber cabinet I will also change the spotted cord and black plugtop to a brown cord with a brown plug.

Other issues are the sound quality - the speaker's voice coil is probably fouled and will require a few bursts of compressed air to clean it. The cone looks to be on good order though. A speaker that still looks brand new after 76 years is nothing short of a miracle. All the electrolytic condensers require replacement. Most of these are the originals, including the big one on top of the chassis next door to the rectifier valve. Most of the smaller-value condensers have been changed at some stage with modern 'yellows'. Odd that recapping has been done on the smaller ones and not the large - perhaps this was also done a long time ago when the electros would have still been serviceable. On the subject of condensers, someone has installed a 2500μF electro running from the 6V6G to chassis. I haven't the benefit of a circuit to verify at this stage but this value seems extra-ordinarily high for a valve radio. Looking at an R27 circuit diagram, it appears this condenser should be 25μF - a much more realistic value I think. This condenser runs in parallel with a 400Ω resistor.

The receiver will then be re-aligned as much as it needs to be. I usually do this by ear with good results. I also need to acquire a replacement dial scale as the familiar globe-burn has affected this set as much as most Radiolette chassis of the era.

This will take care of the easy part of this job. Once the electronics has been taken care of this receiver's cabinet will require a complete refurbishment. The old lacquer will be stripped off, veneer repairs carried out and then the cabinet will be restained and coated in white shellac before receiving a coat of clear lacquer. The chrome dial surround will be buffed up and a new grille cloth installed before the receiver is reassembled ready to go into service. This radio will soon find itself on display as a working unit in my office at work, replacing a 1947 AWA Radiolette 500M which has been the noisemaker for the last five-and-a-half years.

An article on the restoration will then be written for this site.

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A valve a day keeps the transistor away...

Hi Brad,

Re cabinet refinishing, do you use shellac as only a sealer, or do you build up a bit of a shine before spraying the lacquer ?

Also what type of lacquer?

Thanks,

Tim.

42 is a 6F6 so any self bias will be wrong for a start.

One hopes the 2500μF is not on HT as that can easily kill the rectifier.

Marc

Hi Marc,

" ...One hopes the 2500μF is not on HT as that can easily kill the rectifier....."

Why is this??? Does this size cap draw too much current from the rectifier on initial charging?? Or too much leakage current??

Are you high and dry??

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Cheers, Ian

The 2500μF condenser is now part of history though other problems relating to sound still exist. I haven't had time to reverse engineer the 6V6G back to the 42 yet so this job is on hold until time permits.

As for cabinet polishing, I've been known to do a few things, depending on the radio. My first timber retore involved using satin Estapol and it gave a good smooth finish but it probably did the job of subduing the shine too well. This was done on a large HMV table model from the late 1940s - not sure of the model number but its a fairly common type.

On a 1948 (or thereabouts) Airzone Cub I only used shellac but applied quite a few coats. This set has a fantastic look but the small pores show, indicating that the shellac should have been thicker in consistency. The good thing with shellac though is that 'upgrades' are easy and new coats will blend with the existing ones.

I never seemed to find the time to locate a source of more traditional lacquers, nor do I have the time at present to finish setting up my spraying outfit and with this in mind I confine restoration efforts to timber radios where the cabinet is in good nick or bakelite ones, which don't require the same sort of efforts and materials.

Once the repairs are done to this AGE receiver it'll probably get white shellac (I have one bottle and it's very hard to find now) followed by a coat or two of lacquer once I have set up my air compressor.

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A valve a day keeps the transistor away...

Don't know about reverse engineer. If all of the 42 bias is there .... Remove A insert B, much less hassle.

Most of the rectifier tubes specify a maximum value for caps using either capacitive or inductive choke input filters (depending on voltage).

If the capacitor is too big it can "strip" the cathode & cause the valve to fail prematurely.

The original finish if not French polished, was likely Nitrocellulose Laquer. It is still made. I recently saw an "Orthosonic" cabinet re-done using that ..... magnificent. What is so good about this stuff is it's ability to melt into the previous layer. That aids the finish emensly.

I am on the slope of a hill but do have the benefit of "creeks", with around 410mm of rain, these tended to cut the roads, but not to the extent that I could not navigate around on the tractor where needed. That sort of rush only takes a few hours to run off & become someone elses problem.

My drainage etc. is such that I have organised it so the water does not get the house. Worked fine.

Not so for neighbour, spent about 5 hours, re directing (sandbaging etc) the water from the creek next to it. Tractors and us, were knee deep & more in water most of the time. but we won. Albiet I did end up spending the night in outpatients; Due in part to an incident with a winch failure, lifting, tractors and basically doing things that persons with certain physical disabilities, should avoid especially when they were injured when they started.

However, we move on...... some things just have to be made to happen.

Marc

Reverse-engineer = change the valve socket back to the type AWA provided.

I would say most, if not all, Australian radios were sprayed with nitrocellulose lacquer. French polishing would have been too time-consuming and expensive.

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A valve a day keeps the transistor away...

Depending on origin, the commercials were mainly Nitro but in the early sets I have seen a variety. Some were made by smaller operators with a commercial chassis like Slades; who made chasses for that purpose.

Many like like the Max Howed that has trench valves, has a crude finish, which I do not believe is Nitro but that is easy to prove. That has to have the circuit & layout recorded

I am actually trying to identify a home built chassis the may have been a "Reflex" Aegis originally. The aerial coil is Aegis. By reverse engineering the circuit which is clearly "Modified"

The Vetran will have to have the whole layout & circuit recorded (superhet) as it will need to be dismantled to repair some damage and do some conservation work on it and it's seperaate loop antenna (Deutsche Telegraf).

Marc