Forums :: NEW! Web Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently Oct Sun 24, 2021 11:25 am


All times are UTC [ DST ]





Post New Topic Post Reply  [ 6 posts ] 
Author Message
 Post subject: Need repair Audiotronics 300-T classroom tutorette
PostPosted: Sep Sun 05, 2021 11:31 pm 
New Member

Joined: Sep Sun 05, 2021 11:18 pm
Posts: 2
We just bought an Audiotronics 300-T classroom tutorette and the turn table will not turn. We don't want to screw anything up, so I thought I would ask here if anyone might be able to help. We did open it up and discovered a blown fuse. Not knowing what size fuse to get, we are at a stand still. If anyone can help please let me know. Thank you in advance!


Top
 Profile  
 
 Post subject: Re: Need repair Audiotronics 300-T classroom tutorette
PostPosted: Sep Mon 06, 2021 3:58 pm 
Member

Joined: Jan Wed 16, 2013 12:04 am
Posts: 2542
Location: 77001
Tlavery wrote:
We just bought an Audiotronics 300-T classroom tutorette and the turn table will not turn.

We did open it up and discovered a blown fuse. Not knowing what size fuse to get, we are at a stand still. If anyone can help please let me know. Thank you in advance!
1. If you have a blown fuse, there is something in
the circuit that needs repair, or else the fuse would not have melted.

Make sure to leave the AC power cord dis-connected from the AC wall
outlet.

2. Post photos of the record player. Especially of the internal amplifier,
if it is visible.

3. If there is a paper circuit schematic glued onto the inside or
underside of the cabinet, then
we need a sharp photo of the schematic.

Hotwax


Top
 Profile  
 
 Post subject: Re: Need repair Audiotronics 300-T classroom tutorette
PostPosted: Sep Mon 06, 2021 6:32 pm 
New Member

Joined: Sep Sun 05, 2021 11:18 pm
Posts: 2
Ok thank you. I'll do that this afternoon.


Top
 Profile  
 
 Post subject: Re: Need repair Audiotronics 300-T classroom tutorette
PostPosted: Sep Tue 07, 2021 4:20 am 
Member

Joined: Dec Sun 07, 2008 7:05 am
Posts: 4788
Location: Meridian, MS 39307
They made both tube and transistor versions that use the same model number; so, what version is yours? Blown fuses can be caused by; but, are not limited to, shorted rectifier diodes, shorted or very leaky filter capacitors, shorted audio output transistors, and a shorted audio output tube. When a fuse blows, something caused it to blow (even if the cause was by a power surge) and this should be investigated. Never replace a blown fuse with a larger amperage fuse and never jump a blown fuse with foil, wire, etc.

_________________
http://www.youtube.com/user/radiotvphononut


Top
 Profile  
 
 Post subject: Re: Need repair Audiotronics 300-T classroom tutorette
PostPosted: Sep Tue 07, 2021 5:48 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 4790
Location: Boston, MA USA
Sometimes fuses just fail for no good reason. If the fuse is open but not blackened inside, it is likely that the fuse merely fractured. If it is blackened however, it blew from over-current and attention is needed.

-David


Top
 Profile  
 
 Post subject: Re: Need repair Audiotronics 300-T classroom tutorette
PostPosted: Sep Tue 07, 2021 6:31 pm 
Member

Joined: May Sat 14, 2011 5:42 am
Posts: 4222
Location: Ft Worth TX
Quote:
Sometimes fuses just fail for no good reason.
A good reason is stress fracture of the element. Devices with large inrush currents can incandesce the element, however briefly. Repeat this stress enough times and the element lets go.

Have to add that a classroom phono would not typically exhibit this mode, unless say the inrush was
1) cold filaments plus 2) non-thermionic rectifier.

_________________
"Enjoy the fair, George."


Top
 Profile  
 
Post New Topic Post Reply  [ 6 posts ]  Moderator: Alan Voorhees

All times are UTC [ DST ]


Who is online

Users browsing this forum: No registered users and 4 guests



Search for:
Jump to:  


































Privacy Policy :: Powered by phpBB