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 AWA EMPIRE STATE RADIO
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 Return to top of page · Post #: 16 · Written at 5:58:16 PM on 8 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Well I have ordered a couple of the 1.5 K 15 watt resistors . They are out of stock however not to worry I am sure they will arrive in due time. Ian I surprise myself some times with my level of dumbness. I now see your point . I assumed the choke and the field coil would have the same resistance not so . I know the field coil basically serves a double purpose its primary purpose as a magnet and secondly for filtering . I am learning all the time however my learning curve seems retrarded at times .
I learned a lot from the total rebuild of the " LITTLE GENERAL" I have not made a start on this and already find out things I had absolutely no concept of. Not sure how I have survived over the last 73 years. I will need another 73 years to catch up to you guys !
Please be assured I really appreciate everyone's input.
Kind regards Jim


 
 Return to top of page · Post #: 17 · Written at 6:33:11 PM on 8 September 2020.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 563

The last Empire that came through my workshop some 8 months ago, I replaced the field coil with 100mA rated choke.
And from memory no excessive HT volts.
That radio as far as I know is used every day for the local news etc and is still going OK.
Nothing even slightly getting warm, I normally soak test them at least 72 hours straight.
JJ


 
 Return to top of page · Post #: 18 · Written at 7:41:54 PM on 8 September 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2477

Well JJ, your B+ would still have been at least 50 volts up on the nominal 250 it should be. Probably, the 42 would bias itself back a bit which would help the dissipation.

If the field coil has a resistance of 1600 ohms it makes sense to use the same resistor, or close to. It pays not to go over the voltage ratings if you want long term reliability.

But hey, these things kept going with 20% tolerances all over the place.


 
 Return to top of page · Post #: 19 · Written at 10:05:38 PM on 8 September 2020.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 563

Ian, no the plate voltage was around 230 from memory.
No stress anywhere.
Perhaps the rectifier was weak.
I chose the choke to roughly match the resistance I measured of the old field coil.
To be 50 volts up, the choke I used would have had to be a virtual short.
JJ


 
 Return to top of page · Post #: 20 · Written at 9:05:06 PM on 9 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Can anyone tell me the dimensions of the rectangular box that sits next to the 80 rectifier on this Empire State radio please it is missing from this one.
Kind regards Jim


 
 Return to top of page · Post #: 21 · Written at 12:04:04 AM on 10 September 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2477

Tomorrow I'll take a picture of it, with dimensions added.


 
 Return to top of page · Post #: 22 · Written at 9:13:57 AM on 10 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank you Ian.
Regards Jim


 
 Return to top of page · Post #: 23 · Written at 9:55:14 AM on 10 September 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5389

Do remember that unlike many American sets our transformers have taps. If the voltage is a bit high make sure its on the 240 - 260 Volt tap.


 
 Return to top of page · Post #: 24 · Written at 12:07:28 PM on 10 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank Marc.
It will be great if I can proceed to that point.
Regards Jim


 
 Return to top of page · Post #: 25 · Written at 6:03:12 PM on 10 September 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

I don't suppose anyone would have a dial pointer for this Empire State radio . I may have to make one . One side is only half the length of the other. I am thinking both sides should be the same. But what would I know!
Still have not ventured to the under side it looks like a kids fire cracker bundle destined for the neighbours letter box.
I am waiting till I get the manual before I start this. I know these are are good radios ,what I do not know is what the engineer was smoking when he put it together . I need some !
Kind Regards Jim


 
 Return to top of page · Post #: 26 · Written at 8:41:37 PM on 10 September 2020.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7395

Photos uploaded to Post 3.


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

 
 Return to top of page · Post #: 27 · Written at 11:14:29 PM on 10 September 2020.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2078

Thanks for the photos Brad.

Everything is so crammed in there - good luck fixing it!

Looks like the 42 and 80 are touching.

And the knob with a resistor stuck in it.

I'd agree about the dial pointer - it does appear that one end is missing.

Still, it does look interesting... if I was in your situation, I'd look upon it as a challenge, especially as it appears that everything is there.


 
 Return to top of page · Post #: 28 · Written at 7:26:58 AM on 11 September 2020.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 1302

Re the pointer, going on various images on the WWW, it appears complete.


 
 Return to top of page · Post #: 29 · Written at 7:43:54 AM on 11 September 2020.
Gandhn's Gravatar
 Location: Cameron Park, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 409

Yes, the pointer is correct.
If it was double ended, you wouldn't know which end is correct.

Harold


 
 Return to top of page · Post #: 30 · Written at 9:29:08 AM on 11 September 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5389

Agree: Pointer OK.

https://www.bing.com/search?q=awa+empire+state+radio&form=ANNTH1&refig=3eaea70b34b048cdafce6e00a46e2ae5&sp=1&qs=AS&pq=awa+empire+state+&sk=PRES1&sc=1-17&cvid=3eaea70b34b048cdafce6e00a46e2ae5

Marc


 
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