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Breville 330J Restoration Part 1

January 29, 2018 Leave a comment

I picked up this Australian built radio some time ago. It has sat in a carton in my storage for some time. When restoring Dad’s 1935 Ultimate I wondered if I could get some donor parts from this radio, but when I took a look at the condition of the electronics, I decided to restore it. The electronics are in amazing condition. The radio was produced in the late 1940s, possibly 1948.

27066775_1840903212627293_4071677038937855009_nChassis

I removed the chassis from the wooden case and due to the excellent condition, decided to fire it up without replacing the capacitors. I ran it up on a variac and it came to life, with very low audio. The valve line up according to the markings on the chassis is 5Y3G rectifier, 6J8G Osc/Mixer, 6U3G IF Amp and 6G8G AGC, El3G Audio Amp

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5Y3G rectifier socket.

27332373_1840902999293981_817692224466341981_nIF Amp- Actually says 6U3G now that I see the photo
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6G8G or 6B8G RF Amp and AGC

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EL3G Audio amp

The schematic I have shows a slightly different line up and initially it caused me to be confused. I had confused the audio amp with the mixer. The EL3G that is supposed to be in this set is similar in code to the EK2G on the schematic, but anyway I have now sorted it out.

The EL3G is made of unobtainium so someone had inserted a 6F6G which is much lower gain- this would explain the weak audio. So what I need to do is change the EL3G for a 6V6G and change the bias resistor to reduce current draw. I can test to ensure the control grid voltage is around -12V and all should be good.  Unfortunately audiophiles have pushed the prices of 6V6Gs, for their trendy valve stereos, through the roof…. more soon.

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Categories: Vintage Radio

My Dad’s 1935 Ultimate Receiver – Part 2

January 25, 2018 Leave a comment

I returned home to Northern QLD, some 2200 kilometres from where I now live in Sydney, for Christmas 2017. I was working, house sitting and dog sitting, which gave me plenty of time in the evenings and weekends to repair Dad’s radio. Unfortunately some late  received communication meant that I failed to bring my test equipment and tools, so I shipped the radio to Sydney via Greyhound, to be picked up on my return.

Fortunately the radio was unscathed by the bus trip and was promptly placed on my workbench for the investigations to begin. It became immediately clear, that the capacitor I had failed to change had destroyed itself in rather spectacular and gooey fashion and taken out a few other components as it went. An inspection revealed a failed 2A7 mixer and the 57 valve (vacuum tube) had a loose glass envelope. I suspected other damage but could see none.

I replaced the capacitor and ordered replacement valves (tubes). When the tubes arrived I replaced the defective ones, and the rectifier just for kicks. I turned the radio on, the lights glowed, the valves glowed but no sound. hmmmmm. A quick check of voltages found nothing out of the ordinary as far as the mixer and audio amp were concerned.

This made me suspicious that I had an open speaker field coil. A failed coil, either field or in primary, was confirmed by removing the audio amp with the radio on- no click from the speaker. So some further digging around is required…. more in Part 3.

Categories: Vintage Radio

Echophone EC-1

While I still have the restoration of my Hammarlund HQ170 to finish, and a repair of the audio circuit on my Viking Ranger II to complete, as well as a rectifier repair on a Yaesu FT101E, I could not go past this little beauty. While I have older receivers (1935 and 1936), I have been wanting a receiver from the period of WWII now for some time. This little radio was known as the morale radio.

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The original EC-1 was the GI’s radio of World War 2 and it was manufactured by the Hallicrafters company under the brand name “Echophone Commercial.”  It began production toward the end of 1940 and continued in production all through the war.  This model radio was about the only commercial, non military radio that the government allowed to be manufactured during WW 2 and they did it for morale purposes, that is, to provide lonely, homesick and bored servicemen with entertainment.  These rugged little radios have good short wave circuits so the servicemen and women could listen to shows, music and war news no matter where they were in the world.  The EC-1 sold at a  “reasonable” price of about $20 (about a month’s pay).  Actually, for this quality of radio, $20 was a very low price and a lot of GIs got to own them either by buying them outright or receiving them as gifts.

Hogarth
The EC-1 radios were marketed to the GIs directly and through their families to be given as gifts.  Ads for the radios appeared in magazines with a rather over the top campaign featuring a Private (later corporal) Hogarth.  Hogarth was always shown as a hopeless nerd with coke-bottle glasses, but very popular with pretty girls who wanted to listen to his radio. I don’t think this nerdy girl could attract girls with a short wave radio, but those were innocent if heteronormative times.

I may have some modifications to do to the radio when it arrives, most notably for safety, unless the appropriate modifications were done in 1994 when this radio had a major service. Known as an all American 5, the 115V supply is delivered to the 5 valves in series, without a transformer or fuse. One side of the mains chord connects directly to the radio chassis which is isolated from the external box by rubber grommets only. Without a polarised plug to determine which is neutral and which is active, there is a 50% chance of connecting the chassis to the active. Life was cheap in the 1940s :-).

Categories: Daily News, HF, Vintage Radio