I am really enjoying this renovation bug! I have already renovated two of my favourite receivers from the past, the HRO receiver and R1155 receiver. Both are working well and I am quite proud to have these old classics back to life again. My next project takes me back to 1971 when I bought a Hallicrafters SX24 receiver to replace my old R109A receiver. The Hallicrafters covered 1.8 – 30Mhz, my first all receiver. I kept this receiver until 1980 when I gave it away to a friend. I had moved on to buying a Yaesu FT101E at that time.
The Hallicrafters SX24 receiver in my shack in 1978
The Hallicrafters SX24 was a great receiver at the time and I always regretted getting rid of it. I wondered if I could get hold of one these again and renovate it like the one that I had before. Unfortunately, SX24 receivers are few and far between, I never see them on eBay apart from some in America. When I mentioned on Facebook that I was after getting hold of a Hallicrafters receiver, I was offered a Hallicrafters S20R receiver that needed some TLC and renovation. As the S20R is very similar to the SX24 apart from the S Meter and crystal filter and the circuit is virtually the same, I took the challenge.
The Hallicrafters S20R receiver before renovation.
The S20R receiver is working, but needs a lot of work, particularly changing all the capacitors and resistors underneath, this is something that I did with the SX24 many years ago, so I am quite familiar with the circuit and workings of this receiver. The dials on the S20R are very yellow with age and the Perspex windows are warped. All the switches are original and made from wood and need replacing. The chassis is mucky with some rust, but just needs a good cleaning with wire wool or emery cloth. The speaker is original and the cone has been repaired a few times, but it still works after 80 years!
The Hallicrafters S20R stripped down.
I remember spending a lot of time under the chassis of the SX24, I almost know by heart what all the trimmers do in the RF unit, alignment was fairly straight forward. I also remember that the mains transformer burned up one Sunday afternoon and had to be replaced. There were no fuses fitted then, with the S20R I will make sure that fuses are fitted.
I started to replace the components step by step. First replacing the smoothing capacitors and then moving on to different sections of the circuit. I tested the receiver after replacing each section so that I had not made any mistakes.
Underside and above after renovation. The old bulbs have been replaced with banks of LEDs, this makes the dials much brighter than the bulbs.
The case needed some TLC, I managed to mix some enamel model paint to match the colour of the case and touch up the scratches and parts where the paint had worn away. I used T-Cut Turtle Wax to renovate the colour and gloss of the paintwork without removing the decals on the front panel. I also made a decision to change the colour scheme of the Hallicrafters S20R to look like my SX24 by painting the main dial and speaker grill black. I also added a black fabric speaker fret on the front of the speaker. I replaced the dial windows with acetate that I designed on the computer to be identical to the originals. Unfortunately, apart from cleaning I could not do very much with the discoloured yellow dials, but they look much better with the clear acetate windows. I will add the aluminium side trims later, these will be painted black to match the rest of the case.
The renovated Hallicrafters S20R receiver with an external S Meter fitted. This looks and feels very much like my old Hallicrafters SX24 receiver!