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 Unusual radiogram
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 Return to top of page · Post #: 46 · Written at 9:57:25 PM on 7 April 2022.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2017

-- (removed) --


 
 Return to top of page · Post #: 47 · Written at 10:44:44 PM on 7 April 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5257

It is entirely on topic as there are pics in post 1 that are not sharp and Brad mentioned that. Brad and I are both suggesting & demonstrating in good faith, how to avoid that trap. If we put it elsewhere it would not have been seen as it has been mentioned before & keeps happening.

At least complaining about us means some read it and that's a plus.


 
 Return to top of page · Post #: 48 · Written at 4:04:31 PM on 8 April 2022.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7307

All the posts can remain. All are in one way or another relevant to what has been discussed in other posts.


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

 
 Return to top of page · Post #: 49 · Written at 7:48:29 PM on 8 April 2022.
BringBackTheValve's Gravatar
 Location: Linton, VIC
 Member since 30 December 2016
 Member #: 2028
 Postcount: 467

Hey Marcc,

That is one hell of a picture. Perfect clarity mate, if my photos looked that that I would be filling this forum with my experiments and 'restores',
but my blurry I- Pod pics are disgraceful. It's high time I upgraded my camera and photography technique.

Thanks for the the inspiration.


 
 Return to top of page · Post #: 50 · Written at 10:45:24 PM on 8 April 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5257

Yeh! As noted I have been chewing up film & now digital space for a long time. Just on Orchids the Zenza Bronica - Alone with $2500 lenses and a Bellows attachment has chewed through more than 300 Rolls of 120 Roll film mainly on terrestrial orchids and the odd Wedding, Funeral etc. I have worn out several cameras.

Radio Museum got the finished chassis. However, they must have liked it as its posted. However, camera technique, as we described, it just as crucial as the camera. There is no camera that can compensate for bad technique. I have seen some brilliant photos, from some seriously old cameras from WWI.

The idea of the post was to inspire. It is others that judge the image


 
 Return to top of page · Post #: 51 · Written at 9:31:37 AM on 29 April 2022.
Scotty's Gravatar
 Location: Melbourne, VIC
 Member since 26 December 2010
 Member #: 794
 Postcount: 387

Hi all,
An update on this unit, after recapping the amplifier stage, it came back to life and sounds great with plenty of power. I still have an issue with the radio as if only tunes to lower frequencies (ABC 621) moving to higher frequencies, the radio fades out all together.
Suggestions?
Cheers scott


 
 Return to top of page · Post #: 52 · Written at 11:23:53 AM on 29 April 2022.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 544

Should be a fairly lively radio with additional tuned RF stage.
First would be to measure voltages on the three front end valves, as there is a good chance a resistor or two may be way out of tolerance. And then compare with data books or another radio using at least the mixer and IF valves.
Then if possible would be to substitute valves one by one.
If you have a generator you would check the liveliness or not of the IF stage. For fault or drifted alignment.
The way the fault is described the mixer 6AN7 area would be a good start though.
JJ


 
 Return to top of page · Post #: 53 · Written at 4:35:16 PM on 29 April 2022.
Scotty's Gravatar
 Location: Melbourne, VIC
 Member since 26 December 2010
 Member #: 794
 Postcount: 387

Cheers


 
 Return to top of page · Post #: 54 · Written at 10:26:07 PM on 29 April 2022.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5257

Pentagrids (6AN7) tend to loose high frequency due to weak modulation as they die. However, they also die with insufficient volts.

There at this point not be one old waxed paper cap, or electrolytic cap left in it. Some of the resistors in that era were, in batches, not reliable & I have on a couple of occasions, had to replace the lot.

The tuning gang rotor blades shorting is not out of the question. Out side ones being the most vulnerable.

Marc


 
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