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 Companion Radio
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 Return to top of page · Post #: 1 · Written at 2:57:22 PM on 24 May 2016.
Radio Fan's Gravatar
 Location: Grovedale, VIC
 Member since 11 May 2014
 Member #: 1570
 Postcount: 14

Can anybody help me with a circuit diagram of a Companion Radio By Johns of Auckland NZ. It has a valve lineup of 6SK7, 6K8, 6SK7, 6B8, 6V6, 5Y3.and 6U5 Magic Eye. There is something wrong with the tuning, the local ABC station (3LO) takes up 3/4 of the dial length with the other stations cramped down the high end of the dial .I have tried aligning it( assuming a 455Kc IF) but no improvement. It has been fiddled with some time in the past so I have no idea if connections and component values are correct. I will get Brad to upload images.

Thanks .

Companion Table Radio
Companion Table Radio
Companion Table Radio
Companion Table Radio


 
 Return to top of page · Post #: 2 · Written at 5:24:17 PM on 24 May 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5302

Can anybody help me with a circuit diagram of a Companion Radio By Johns of Auckland NZ

Suggest you contact New Zealand Vintage Radio Society, here: http://www.nzvrs.pl.net/.


 
 Return to top of page · Post #: 3 · Written at 8:48:23 PM on 24 May 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3791

The problem is likely to be to do with the padder if fitted, wrong components, or the wrong Pentagrid like its a 6J8 not a 6K8, it does that sort of thing. Not the IF.

You will need the circuit to see just what has been monkeyed with.

Marc


 
 Return to top of page · Post #: 4 · Written at 3:54:02 PM on 25 May 2016.
Radio Fan's Gravatar
 Location: Grovedale, VIC
 Member since 11 May 2014
 Member #: 1570
 Postcount: 14

I have tried the NZVRS but no luck. Apparently Johns of Auckland specialised in kit radios which could be assembled by the purchaser or brought already assembled. This may explain the lack of circuit diagrams. Marcc, it states a 6K8 on the valve layout sticker and I have tried a standard 425pf padder so must be a wrong component somewhere else. Don't know what happened to the photos, maybe they are still coming.


 
 Return to top of page · Post #: 5 · Written at 5:43:32 PM on 25 May 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5567

Photos have arrived safely and will go up tonight. Smile


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 6 · Written at 9:07:19 PM on 25 May 2016.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5567

Photos uploaded.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 7 · Written at 9:42:16 PM on 25 May 2016.
Robbbert's avatar
 Location: Sydney, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 1094

Aha, photos.

The plate on the back showing the valve locations is easy to read, can't really argue with it.

It's obviously been worked on and all the small components have been replaced already.

16 trimcaps to play with, a twiddler's delight.

4 shortwave bands and AM.

Question: do the shortwave bands show the same problem, or are the stations spread out correctly?


 
 Return to top of page · Post #: 8 · Written at 11:32:56 PM on 25 May 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3791

Not happy with the mains cable It appears not to be anchored? Impending disaster, no anchor no conformance with regulations. That top cap on the 6B8 will short to the Goat Shield, If you can get the terminal off, put shrink tube on it and include some of the braid.

Over all the layout looks chaotic. Wonder what they were drinking when they designed it?

Marc


 
 Return to top of page · Post #: 9 · Written at 9:01:06 AM on 26 May 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5302

Over all the layout looks chaotic.

Yep but, as Radio Fan has mentioned, the Johns company supplied kit radios so it's probably a DIY effort.

Rather attractive cabinet, nonetheless.


 
 Return to top of page · Post #: 10 · Written at 2:12:42 PM on 27 May 2016.
Radio Fan's Gravatar
 Location: Grovedale, VIC
 Member since 11 May 2014
 Member #: 1570
 Postcount: 14

Marcc, the mains cable is anchored, just hidden by the chassis lip. I managed to fix the fault, IF's had 2 peaks and I aligned it to the wrong peak. Broadcast band now working as it should. Found the 2 higher shortwave bands not working so more work to be done. The coil switching is a nightmare to work out as there are only 2 sets of coils for 4 bands. I also found that the RF stage is bypassed on the shortwave bands, very strange. Will have to patiently trace the switching cct out.


 
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