Eastronic 6 Transistos (sic).
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Bought a tinny tranny for £7.99 off eBay. I was intrigued by the telescopic aerial on an AM only radio... it's not connected to anything, maybe the enclosure is used for FM versions as well. It was sold as not working, I found it did work through the earphone (2.5mm!) and after desoldering the speaker measured open cct. I tweezered the paper voice coil cylinder out and found the break on the coil was at the start of the winding so I wound it out enough to solder it and crammed it back on to the magnet. So now it works, the reception is as poor as you might expect and the speaker does click a bit when I can find a loud enough signal.
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Re: Eastronic 6 Transistos (sic).
Quite a few no-name Hong Kong LW/MW radios had pointless telescopic aerials in the 60s and 70s. Presumably the makers thought it would increase sales.
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Re: Eastronic 6 Transistos (sic).
You could connect the telescopic to set 0V via a few turns wrapped round the centre of the ferrite rod. It probably wouldn't make things any worse.....
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Re: Eastronic 6 Transistos (sic).
Most of these cheap HK sets actually had reasonable performance, so if it's really awful then there's probably something wrong with it.
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Re: Eastronic 6 Transistos (sic).
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Very few radios in the US have LW, so I have little experience with it. Always learning something new from this website. :wave: Dave, USradcoll1 |
Re: Eastronic 6 Transistos (sic).
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" if it's really awful then there's probably something wrong with it." it's pretty bad, I'll have a closer look, I didn't like the way the antenna coils were hanging off the ends of the rod and I could measure the electrolytic out of cct. |
Re: Eastronic 6 Transistos (sic).
If the aerial coils are hanging off the end of the rod, it could be worth adjusting the MW one for a peak response to a station near the LF end of medium wave and the LW one to peak up R4 LW. Certainly if they're wrongly positioned, sensitivity will be down. Use a few drips of candlewax or even a wrap of sellotape to hold them in position when tweaked.
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Re: Eastronic 6 Transistos (sic).
Dave, a telescopic aerial is actually *less* likely to be useful on LW. If the aerial isn't completely cosmetic, it may have been added for SW use. These radios often covered BC and SW in markets where LW wasn't used.
The HK manufacturers were very focussed on the UK market in the 60s and early 70s though - it was the only significant part of the British Empire left then, and 1997 seemed a long way into the future. |
Re: Eastronic 6 Transistos (sic).
Moving the LW coil made a noticeable difference, so much so I had to replace the clicky speaker with one off a Chinese kit MW radio I had previously ruined trying to convert it to LW... When I came to switch this on it wouldn't work until I had used some contact cleaner on the on/off switch - I wonder if the waterproof PVA I had used for gluing the clicky speaker back in gave off a vapour which coated the contacts... Moving the MW coil made no difference but the MW stations available here are very weak to begin with so possibly beyond this tranny's ability, I might revisit this next time I drive to the big smoke (Inversneckie).
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Re: Eastronic 6 Transistos (sic).
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Picked up the same radio a few months ago, with Paul Sound logo and MW/CB.
Ian |
Re: Eastronic 6 Transistos (sic).
Interesting variant. You don't see many radios with CB coverage in the UK from that period, as it was illegal (and still is for AM). My guess would be that it's a model for the American market which somehow made its way here.
It explains what the aerial is for anyway. |
Re: Eastronic 6 Transistos (sic).
I think AM and SSB is now legal in the UK for use on the EU band
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Re: Eastronic 6 Transistos (sic).
I stand corrected. I've never had much time for the CB thing.
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Re: Eastronic 6 Transistos (sic).
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I was able to find the sweet spot for the MW coil on the ferrite rod using an AM signal booster I stumbled across on my constitutional yesterday. For a bit of fun I videoed a demonstration of this signal booster, first MW then LW.
https://youtu.be/aT8Vo4VcdR0 https://youtu.be/yUZTzHhGTKE Comparing this with a smaller HK AM radio Ingersoll XK-791 which works so much better, see photo, the ferrite rod on this one is only slightly shorter but is thicker, otherwise the component count looks similar. More evidence there is indeed something wrong with this one. By ear I'd say it has a poor signal-to-noise ratio so I'm guessing it's a problem with the circuit around the first stage transistor marked 901. I've no schematic for it but this radio should be simple enough for even me to reverse engineer. More to follow hopefully. |
Re: Eastronic 6 Transistos (sic).
It's actually likely to be something simple like a dirty wavechange switch. The transistors are probably general purpose types like the 2N3904 if you need to change them, though they might have 'Japanese standard' ecb leadouts.
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Re: Eastronic 6 Transistos (sic).
Hong Kong transistors might also use CBE layout (as opposed to European EBC).
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Re: Eastronic 6 Transistos (sic).
I am surprised you had all that crackling noise out in the wilds - thought it might have been an electric fence at first but the top strand does not seem to be insulated - although it is separate from the mesh.
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Re: Eastronic 6 Transistos (sic).
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"It's actually likely to be something simple like a dirty wavechange switch." - Good point. So I checked it but it wasn't dirty, at least I've now given the contacts a good polish and lube so it'll be good for another 40 years If I can fix it, I still haven't checked the electrolytics out of circuit, there's one decoupling the IF stages, that's next I think. |
Re: Eastronic 6 Transistos (sic).
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I'm putting this to one side for a while, it might just be a poor quality radio. I poked around it quite extensively, replaced a resistor which looked wierd and measured about 15% high in the IF section. Tried dropping in a replacement RF transistor off that abandoned Chinese kit radio. None of this made any noticeable difference.
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