Forums :: Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives :: Books
Support This Site: Contributors :: Advertise


It is currently Nov Thu 27, 2014 5:21 am


All times are UTC [ DST ]



Post New Topic Post Reply  [ 12 posts ] 
Author Message
 Post subject: Left Channel problem - Saba Continental 410 US (Freiburg 14)
PostPosted: Mar Sat 10, 2012 9:37 pm 
New Member

Joined: Feb Mon 13, 2012 8:13 am
Posts: 18
I am carrying out restoration of my Saba Continental 410 US (Freiburg 14) and have completed cleaning and lubrication job. There are a number of issues that have surfaced. I am going to prioritize these. At the moment I am going to address following three. Your help is needed:

1. Left channel (3speakers) is working at less than 25% of the level of right channel (not enough volume and quality of sound), both for radio reception and phono.
The mono/stereo switch is working alright. While playing phono, switch in mono mode blends in the two channels at preamp stage and is heard through the right channel speakers (2 speakers). The speakers of left channel stay feeble. Also I have checked through left and right speakers connection at the back with same result. I also tested out swapping, right or wrong, of the two EF 86 and two ELL 80 tubes. No change was noticed.

2. On/off switch was not functioning. Solenoid and the switch were cleaned without any success. It appears that the solenoid is not getting power/signal from the push button switch. By flicking the solenoid with finger activates on/off.

3. Voice/ music switch has similar problem as in '2' above. Solenoid is not getting power/signal from the switch. I have to manually move the solenoid for changing voice/ music modes. The switch is not functional.
Thanks,
Asif S


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Sun 11, 2012 2:27 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 15804
Location: ID 83301
Time to replace some capacitors .


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Sun 11, 2012 2:34 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 329
Location: Vienna, VA USA
Hi,

If possible, I suggest you test all tubes first. If you have no tube tester available, first replace the preamplifier ECC83 tube with a new one or a good used one. If this does not help the problem you will have to measure all the voltages in the output section of the set. Also, replace C422 and C423 capacitors (22nf each) from the two plates of the ECC83 to the 1k and 120k resistors leading to the G1 of each ELL80. This may possibly improve your sound problem.
By the way, do you have a fax machine, so I could send you pictures of the glass dial?
ps: On my schematic the C422 is marked as R422. That is an error and should be C422.

_________________
George G.


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Sun 11, 2012 2:55 am 
Member

Joined: Dec Sun 16, 2007 4:59 am
Posts: 362
Location: Minneapolis
I've worked on Saba 400's and 200's. If memory serves, there is a balance control on the back of the metal chassis. It is a plastic rod that extends to the control mounted toward the front of the chassis. Try rotating this control and listen for a shift in sound.

If this is to no avail connect a stereo source like a CD player or iPod to the phono-tape input on the back of the set. Sometimes weak output is due to the multiplex unit rather than the audio unit.

The solenoid you reference is a delicate device. I've had some success with carefully cleaning and lubricating the pivots that the solenoid arm rotates on. If moving the solenoid arm causes it to close positively and activate the radio I suspect that you have power to the unit.

These are incredible radios. Well worth the effort you are investing. Good luck.

_________________
"CIVILITY IS RECIPROCAL"


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Sun 11, 2012 9:36 am 
New Member

Joined: Feb Mon 13, 2012 8:13 am
Posts: 18
Hi George,
Thanks for your inputs. I'll try to carry out troubleshooting step-by-step as recommended.
My fax No. 92-21-3584-1876.
Regards,
Asif S.

GSD,
Hi!
I have tested out connecting a turntabe through the phono jack and in stereo mode. The channels output is as I mentioned , left channel less than 25% volume of the right channel. The stereo balance at the back of the radio is functional and shifts the speakers output, slightly (not totally) to left or right speakers, but the left channel overall output stays below the right channel by less than 25% volume and an effort has to be made to hear it or to confirm its working, especially when playing classical music.
Thanks,
Asif S.


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Sun 11, 2012 4:47 pm 
Member

Joined: Dec Sun 16, 2007 4:59 am
Posts: 362
Location: Minneapolis
Have you measured the plate voltage of each output tube? The 200 that I repaired had an open primary on the left-channel output transformer resulting in no plate voltage on the affected channel.

_________________
"CIVILITY IS RECIPROCAL"


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Sun 11, 2012 9:55 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 3833
Location: Malone, New York USA
...As a general FYI, this radio has mylar tubular capacitors, so there's no logical reason for a capacitor replacement en masse.
SABA transitioned to mylar from foil/paper the model year prior.

The only two caps that should be be verified for use are the motor phase lag and tuning (motor windings) caps.
Depending on the provenance of the particular radio, it would have either .22uf (for operation on 60 hz) as issued for those radios destined for sale in North America, or .33uf caps for operation on 50 hz as found in Europe and other points East.

Tube swapping between channels makes perfect sense. If the symptom didn't follow the tubes, then there is an issue in the circuitry. (Assuming the balance control is, in fact, centered.)

Ha-ha! Reminds me of a know-it-all some months back who argued the balance control couldn't be where I told him it was, in the rear of the chassis.


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Mon 12, 2012 4:30 am 
Member

Joined: Sep Thu 23, 2010 6:37 am
Posts: 6119
Location: Powell River BC Canada
With a sin wave of 1 kHz into the phono input, L+R, trace levels to the grids of the output tubes. If they track
well, check the output transformers by swapping left for right. Are the feedback circuits are both in good
condition? A badly gassy ELL80 might damage OPT and the only way to know is try another.

_________________
de
VE7ASO VE7ZSO
Amateur Radio Literacy Club. May we help you read better.
Steve Dow
ve7aso@rac.ca


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Mar Tue 13, 2012 8:34 pm 
New Member

Joined: Feb Mon 13, 2012 8:13 am
Posts: 18
Gentlemen,
Hi!
This is to give you an update.
Have cleared items # 2 & 3 ie on/off switch and voice/music switch after careful cleaning and lubrication of the two solenoids including cleaning of push button contacts which were fouled with severe dirt. These switches are working very smoothly now.

I am continuing to tackle 'Left channel problem' based on the ideas given and trying to locate ECC 83 and ELL 80 in the local market (Karachi, Pakistan) for testing. Any further ideas/ inputs help, more of spoon feeding as I am lacking knowledge of radio, amplifier/ electronics, would be appreciated.
Thank you,
Asif S.


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Apr Wed 04, 2012 3:39 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 329
Location: Vienna, VA USA
Hello Asif,

My son has finally createdd a beautiful reproduction of a Saba 410 dial in three parts. Especially, the matching of the colors was difficult but it is all done now. If you want to, send me your Email, I will send you the information.

_________________
George G.


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Apr Wed 04, 2012 7:42 pm 
New Member

Joined: Feb Mon 13, 2012 8:13 am
Posts: 18
Hi George,

Great! My e-mail address is: asifsaeed63@hotmail.com
Kind regards,
Asif S.


Top
 Profile  
 
 Post subject: Re: Left Channel problem - Saba Continental 410 US (Freiburg
PostPosted: Apr Fri 13, 2012 9:46 pm 
New Member

Joined: Apr Fri 13, 2012 9:25 pm
Posts: 1
Gentlemen,
Just discovered this site and joined immediately. I've just acquired a SABA Continental 410 US like being discussed here. Mine has different issues and I need a schematic and English alignment procedure. I noticed George G from Vienna mentioned one. Could you Please help?

I restored a SABA 300 Automatic Stereo 11 just before this one and there are a number of circuit changes. I have the English alignment procedure for that one is anyone needs it.....and yes the balance control is on the back of the 300 and 410.

Thanks,
Dave B.


Top
 Profile  
 
Post New Topic Post Reply  [ 12 posts ]  Moderators: Marcc, Norm Leal

All times are UTC [ DST ]


Who is online

Users browsing this forum: voroush and 13 guests



Search for:
Jump to:  
















Privacy Policy :: Powered by phpBB