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 AWA RADIOLA B42 Sevice information required.
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 Return to top of page · Post #: 16 · Written at 6:28:37 PM on 3 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6882

I do not usually shotgun things it was an act of sheer desperation

Understood. I generally avoid smashed-up gear. I have reluctantly taken on a few hopeless cases as love jobs, but I didn't enjoy the experience and prayed that they would not be boomerangs.

BTW: Araldite on the table cloth would get most of us shot at dawn, without a trial.


 
 Return to top of page · Post #: 17 · Written at 7:11:21 PM on 3 March 2019.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Hi GTC.
I bought it on ebay the previous persons board repair was so bad the mounting posts were bent out to fit in a couple of screws. I will continue on a bit longer or till I run out of table cloths. I can't win. I only moved onto the dining room table because the dog gets the sulks when I go into the garage. He was nowhere to be seen when I required some support.


 
 Return to top of page · Post #: 18 · Written at 8:04:28 AM on 4 March 2019.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 1370

"run out of table cloths"

I avoid the kitchen table mostly but sometimes you just need to spread things out. Bought a large sheet of thin board from Bunnings, and got it cut to size. If you need to move off the table, shift all the heavy stuff such as the radio chassis, put an old sheet or blanket over the remaining small bits and pieces and small tools, and carry it off. Can then easily start again by carrying the board back, take off the sheet or blanket, put back the heavy pieces.


 
 Return to top of page · Post #: 19 · Written at 3:48:11 PM on 4 March 2019.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Hi STC 830 Good idea.
Will talk it over with the dog


 
 Return to top of page · Post #: 20 · Written at 4:08:52 PM on 4 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6882

Will talk it over with the dog

Puts me in mind of Fred Basset.


 
 Return to top of page · Post #: 21 · Written at 5:01:30 PM on 4 March 2019.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Eureka!!!!

I have found it all working!! The problems with this were a very large crack in the circuit board which had been badly repaired. One speaker connection broken off and an open circuit on the ferrite rod TR1which is in the base emitter winding on transistor VT1. I had unpicked part of this and repaired the winding however the radio still did not work. In desperation I placed a wanted add in the for sales and wanted section. Monochrome answered and asked me what was the problem with the ferrite rod. I wanted to make sure of the problem before I responded, so I revisited what I had done and I discovered when I reconnected the repaired end of the winding I had accidentally connected one end to the ground terminal instead of the Junction R1 10k and C6 0.01. The other end of this Junction goes to ground. This is why the the biasing was all screwed on VT1 resulting in none operation. I nearly reached the point of giving up. Had Monochrome not asked me what the problem was with the ferrite rod I would not have back tracked.

I bought this on ebay for $10.50 condition not workkng. That is why I bought it. I wanted something interesting to repair however I was not expecting multiple faults of this magnitude. However it is now a very presentable working early Aussie radio and I am very happy I persisted with it. I might see if Brad can upload a photo. I like early 60's Aussie transistor radio's.
Kind regards Jimb.

AWA B42 Transistor Radio


 
 Return to top of page · Post #: 22 · Written at 5:08:30 PM on 4 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6882

Good to hear. In my early twenties I used to get told "Patience is a technician". Combined with a logical approach, it is true.


 
 Return to top of page · Post #: 23 · Written at 12:02:03 AM on 5 March 2019.
NewVista's avatar
 Location: Silver City WI, US
 Member since 10 May 2013
 Member #: 1340
 Postcount: 977

This radio seems unique with the push pull loudspeaker. Quite collectable also! The push pull speaker would be lower distortion and no O/P transformer is an added increase in fidelity! Was speaker made in-house by AWA/MSP?


 
 Return to top of page · Post #: 24 · Written at 6:23:04 AM on 5 March 2019.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Hello NewVista.
Not sure it has no sticker on it. It has RK4 on the back of the speaker.
It may have some fidelity benefits, how ever from my point of view I hate them, because they are prone to going open circuit and you can't just replace it with a standard speaker of similar size. It is 80 ohm and centre tapped. They may have been easily replaced 50 odd years ago, not so now. I had an HMV nipper gram that had an 30 ohm centre tapped speaker and it took years to find a replacement.
Regards Jimb.


 
 Return to top of page · Post #: 25 · Written at 6:07:39 PM on 5 March 2019.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2628

Yes they were made by MSP.

MSP (Manufacturers Special Products) was the component division of AWA and they also sold to other manufacturers.


 
 Return to top of page · Post #: 26 · Written at 2:06:06 AM on 6 March 2019.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7548

Photo uploaded to Post 21.


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

 
 Return to top of page · Post #: 27 · Written at 5:39:55 AM on 6 March 2019.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank you Brad.


 
 Return to top of page · Post #: 28 · Written at 12:34:44 PM on 6 March 2019.
NewVista's avatar
 Location: Silver City WI, US
 Member since 10 May 2013
 Member #: 1340
 Postcount: 977

Cool that AWA also made that speaker!
AWA had a hi fi speaker (done in walnut & dark grille fabric) in early 70's that was omnidirectional (trendy idea at the time.)
It had a lower bass unit with downward firing woofer [made by Fostex] plus an upper section that had MSP midrange speakers on all four sides plus a downward firing dome tweeter above a conical dispersion piece for omni-direction.


 
 Return to top of page · Post #: 29 · Written at 3:01:17 PM on 8 March 2019.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2628

Yes, MSP also made guitar speakers at the time.


 
 Return to top of page · Post #: 30 · Written at 6:40:38 PM on 8 March 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5595

Where there is a crack in the board. I will normally put a slight loop in the wire I use to bridge the gap in the tracks.


 
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