HFL / AeroRex
As-found photos of an AeroRex superheterodyne based on the High Frequency Labs (HFL) “Nine-in-Line” superheterodyne kit. Robert Lutz picked this up for me at an auction in the Kansas City area in November, 2022 and I hauled it back to Utah with Rick’s superhets. Two of the original transformers were replaced early on. This was a barn find radio and the cabinet, in fact the entire radio, needs extensive restoration. It will be one hell of a superhet when it’s finished though! The engraved panel is something else and it’s in excellent condition (under all the dirt and grime). The cabinet is super deluxe and massive!
This page was added to the site on January 26, 2023
October 20, 2023 Update:
Restoration
The two pictures above were taken by Bob Lutz before I ever saw the AeroRex. The radio was quite the basket case! Some mice had been inside the cabinet and every nook and cranny of the radio had dead spiders! Not visible here, but the frames of the variable capacitors were corroded and the bakelite of the IF transformers were damaged by mouse urine. Most of the transformers were bad. Luckily for me, Rick had an entire set of transformers that I obtained when I purchased his superhet estate from Bob Lutz!
Picture of the right side of the cabinet that I took before I started to work on the radio. This side was damaged more than any other part of the radio. At first I was wondering how I would ever get this thing repaired and have it look somewhat decent!
I wasn’t lying when I said dead spiders were located in every nook and cranny! The photo at the left shows what I saw when I removed the first tube socket. Dead spiders and spider webs. The photo at the right shows a group of dead spiders in one of the rheostats. Bob had cleaned up this radio before I got it, but some things are impossible to clean without a complete overhaul.
Two views of one of the “Perlesy” tuning capacitor. These are high quality tuning cabacitors and the plates are cast aluminum. I tried cleaning them in a bath of circulating cleaning fluid for several hours, but this did not remove the corrosion that was on the metal. I then took a bastard file and filed the corrosion away. Next, I started sanding the aluminum, starting with #100 grit and working up to #2000 grit. It was a simple process to polish the aluminum from there. The tuning capacitors look like new now.
The finished radio. The front panel, dials, and knobs all turned out very nice with a good cleaning and polishing. The dial pointers were a little more difficult to restore since they had a heavy crusted patina on them. I’m a guy who likes a little patina on an original un-restored radio, but in this case the crusty patina had to be fixed. I took some Q-tips dipped in a lime-a-way solution and gently rubbed the patina off. This left the brass pointers with a dull red color. With a little bit of buffing the the brass really started to shine!
Side view of the restored AeroRex superheterodyne. The first thing I tried on the lid was the “soak and” clamp method of removing a warp. This was not successful at all. The lid would not soak up very much water at all, which I later assumed to be the construction style of the lid. The lid has a fancy trim piece of wood attached to each side, and then a nice wood veneer was applied to the top to hide the difference between to main lid and the trim pieces. The glue for the veneer was stopping the lid from soaking up water. I would have to make a complete lid from scratch. That’s what I should have been thinking in the first place!
To form the main part of the lid I purchased two pieces of walnut 36” by 7” by .75” and glued them together. When the glue dried I cut the lid to the proper size. I cut the fancy wood trim off of each side of the original lid to attach to the new lid. Since the right side trim was completely destroyed, I cut a section of trim out of the back piece to use for the side. I had to make a reproduction piece of trim to fill the back. After the side trim was complete I installed a walnut veneer and refinished. That’s the short story, and I’m sticking to it. But wait, I need to say something about the onlays. I used the original onlay for the top middle piece and purchased the corner and side onlays from eBay. The pieces from eBay were too thick and the sides needed to be trimmed. I worked with the onlays to match the original onlays on the front columns of the radio.
Inside view of the completed receiver. The last audio transformer (that I obtained from Rick’s estate) is bad and I will either have to remove it from the case and repair it, or stuff the case with a replacement transformer.
Two angle views of the inside chassis. In the photo directly above, you can see three little marks engraved on the upper right corner of the chassis. At this time I assume these marks indicate serial number 3. This radio was professionally made by some shop or company.
Two additional views of the chassis. From the photo directly above it can be seen that this set was made by a professional builder. I’ve never seen such care and professionalism in wiring a radio chassis!
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