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7th Dec 2016, 1:41 pm | #1 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
Posts: 597
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Hacker Sovereign 2 Motorboating
Well, after quite a lot of work on it, I got a Hacker Sovereign 2 (S/N: 21349) back together again, put some batteries in and switched on.
VHF working perfectly, nothing on LW and motor boating/howling on MW. Listening with another receiver, no LO on LW and you can hear it sort of starting and stopping on MW. Read a few threads on here and it turns out to be C21 on the 470kHz IF amplifier. At 12V working the original doesn't really seem to be up to it so no wonder it fails. Seems to be a common problem on these sets. The one that came out is a DALY 350uF 12V and the one that's gone in is a Dubilier 330uF 50V. Hope someone finds that useful. Change it anyway I would say! John
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7th Dec 2016, 8:00 pm | #2 |
Dekatron
Join Date: Jul 2007
Location: Evesham, Worcestershire, UK.
Posts: 4,241
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Re: Hacker Sovereign 2 Motorboating
That sounds very familiar
The voltage rating isn't so much the problem, but those blue DALY (and red Elkomold) types definitely are "change on sight", no matter where you find them. They leak heavily and really upset the DC conditions in the RP18/30/31/etc audio amps. Fortunately, by the time of the Sovereign II, those types were fairly rare (and almost always only found on the AM board if anywhere). In the Sovereign I, however, it's another story... The blue Philips types are usually fine, and the miscellaneous Japanese caps found in those sets seem to be pretty good as well. Getting at that capacitor can be a little bit awkward, but as it's not terribly visible, I'm less fussy about what type of replacement I use (usually a modern radial type). Well done on the fix Mark |
7th Dec 2016, 8:21 pm | #3 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
Posts: 597
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Re: Hacker Sovereign 2 Motorboating
Hi Mark,
Thanks for that. Useful information there about capacitors. The radio was in a box of two Sovereign 2's and two Sovereign 3's given to me by 'sp10mk11'. I've managed to make one good one from the two Mk 2's. The other one is an earlier AF117 model. Neither had an aerial but the Maplin LB10L looks quite good. Its shorter but does reach the P clip comfortably. No tuning scale for the other so I'll be on the look out for a wreck! Both the 3's have poor tuning scales but one has the aerial and the battery holder so I haven't given up with them! Cheers John
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