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 AWA EMPIRE STATE RADIO
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 Return to top of page · Post #: 31 · Written at 9:32:59 AM on 11 September 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 1313

Nice photos JimB.
Looks like plenty of room to mount the choke and filters into a box on top.
The chassis needs preserving to keep all the stickers on the back original.
A good soft brush in kero/turps to clean off the muck without damage, then a clear coat over the top to preserve.
The other top bits like cans could do with a lick of AWA paint.
Replace / refurb speaker will be the go.
The wiring underneath should be ok, just get rid of the daggy caps and out of spec resistors.
Yep, the pointer looks original to me.
But get it going electrically first to prove the coils and valves are ok.

Fred.


 
 Return to top of page · Post #: 32 · Written at 10:38:00 AM on 11 September 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2477

That's in MUCH better condition than the one I have on the go at the moment, automotive cut and polish on the crusty bits only might be the go.

Still have to take that picture.

I seem to recall seeing replica square metal boxes for those sets. Steve possibly??

They originally held the filter caps and a few other bypass caps as I recall.


 
 Return to top of page · Post #: 33 · Written at 11:00:45 AM on 11 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank you Brad for the photo upload. I would also like to thank you all for your advise and encouragement. The thing is if it was mine I would have just ripped into it ,however I am doing this for some one else and I don't want to risk it not working at the end of the day.
Although I am doing it for someone else,my motivation is I need something to do always . Sometimes I tend to stress out too much.
I am glad you all confirmed the pointer is correct, it makes sense about knowing which end it is pointing to.
I have another question, the speaker transformer I am using is higher than tha original can anyone tell me how much clearance there is from the top of the chassis to the inside top of the case . Was the speaker just clearing the top of the case or is there some headroom.
I left the case with Tony H and he is back in Sydney and the case is in his house in Wollongong. I left him the case because my space is limited and I did not want to risk it falling off somewhere and getting broken. It was a bit stupid because when you are improvising parts you need the full picture. I will try Steve for the metal case.
Kind Regards Jim.


 
 Return to top of page · Post #: 34 · Written at 1:36:33 PM on 11 September 2020.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 1302

The speaker appears to clear the top of the cabinet by something like an inch going on photo in this ebay listing

https://www.ebay.com.au/itm/163588419298

The speaker transformer is in the way but should be of some help. Its definitely not hard up against the top of the case, assuming it is an original speaker.


 
 Return to top of page · Post #: 35 · Written at 7:10:26 PM on 11 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thanks STC830.
I wish I brought the cabinet back with me . It does seem to have good clearance . This had a 5 inch speaker most had a 4 inch so Still not sure . I will have to get the cabinet before proceeding too far.
Kind regards Jim


 
 Return to top of page · Post #: 36 · Written at 8:03:13 PM on 11 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

I think I am in trouble with the height from the chassis top, to the top of the speaker transformer 165 mm .
Thoughts please . I feel I am making zero progress with this it is so cramped and squashed you need to be a micro surgeon to work on it.
Steve was not able to help with the box next to the 80 rectifier valve so I need take dimensions of that box.
Regards Jim


 
 Return to top of page · Post #: 37 · Written at 12:23:17 AM on 12 September 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2477

A tip - unscrew the sides of the chassis and hinge them down! The manual suggests this.


 
 Return to top of page · Post #: 38 · Written at 12:41:02 AM on 12 September 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5389

Ok! That chassis threw me off, I have actually had an R28 chassis pass under my nose. With it same chassis variant may have appeared in Radio Waves but August 2014 Silicon Chip has one feature & the article is gettable.

R28 has not got the bean cans around the valves, they are caged. Original speaker is mounted on ply (Marine ply would do) and there should be a bracket behind the speaker to take the weight those struts can't. Many modern speakers have a different magnet style and you may be able to set a frame, or ply onto that rear bracket for the transformer.

Marc


 
 Return to top of page · Post #: 39 · Written at 1:20:41 AM on 12 September 2020.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2078

QUOTE: August 2014 Silicon Chip has one feature & the article is gettable.

Hey you're right... it's on my site

http://messui.polygonal-moogle.com/valves/SC201408.pdf

It can be seen from this article, that your radio is missing the Local/Distant switch that should be in the hole in the back.


 
 Return to top of page · Post #: 40 · Written at 9:27:05 AM on 12 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank you all again for your contributions.
Tony H is back. In Wollongong today So I will pick up the cabinit. That will reduce my anxiety levels I can see what else may crop up further down the track. I made up a back support bracket for the speaker with a round hole in the middle to fit over the magnet the top of the bracket is folded over at right angles close to the magnet and the speaker transformer is mounted on this . I am aware of the missing local distance switch. I will need to look around for a suitable metal switch similar to the original, anything else would be out of place.
I think down the track there maybe other missing bits the dial lamp holder is missing and lots of wire hanging out.
Kind regards Jim


 
 Return to top of page · Post #: 41 · Written at 10:21:08 AM on 12 September 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2477

 
 Return to top of page · Post #: 42 · Written at 4:43:35 PM on 12 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank you Robbert for the article and thanks Ian for the switch information. It appears to be a USA website but yes there is a switch there if I can't find one elsewhere.
Well I picked up the cabinet from Tony H this afternoon and yes it fits in nicely still have a out 10 mm clearance so I am happy that it will look good. I now need to make a box to replace the missing one next to the 80 rectifier I can get a good idea now of the size from the pictures still have a problem, filter choke plus resistor may have to be used. Ian suggested a nice 1600 chassis mount resistor and some caps to replace the field coil. I ordered the resistor however there is no stock I will be too old to use it by the time it arrives, not impressed with Element 14.
The alternative may be the choke I have plus a 1k 10 watt horrible square section resistor which won't be as easy to mount. So I guess a little positive progress has been made.
Regards Jim.


 
 Return to top of page · Post #: 43 · Written at 2:26:48 PM on 14 September 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2477

Jim don't let the US location of that site worry you, I order on line from them and get delivery by mail often quicker than local mail. Never had a problem, I got a bad NOS 1S2 from them once and they replaced it pronto no questions asked. Great service.

Re the resistor and choke, be aware that putting a resistor directly in series with a choke diminishes the effectiveness of the choke because it lowers the Q of the circuit. It will be wasted effort. Just use a 1500 ohm 5w from Jaycar (CAT.NO: RR3302) and up the 2nd filter cap slightly.

Are you OK for a speaker and transformer?


 
 Return to top of page · Post #: 44 · Written at 3:21:33 PM on 14 September 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5389

Confirmed I was right: Have that copy of SC.

Beware when buying toggle switches. AC & DC ones are not quite the same in many cases. DC can arc over in an AC switch.

That one operates by adding more self bias to the Valves.

Marc


 
 Return to top of page · Post #: 45 · Written at 4:22:58 PM on 14 September 2020.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 1302

Robbbert, your Silicon Chip article says that an Empire State appears in The Castle. So if you feel like a break Jimb might be worthwhile looking for it.


 
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