Need help with a crosley 516
Page 1 of 1
Need help with a crosley 516
I am just getting started on repairing old radio's and could use some help on a crosley 516 I am working on....I am def learning as I go, so be patient. I picked this radio up a while ago and have been repairing obvious problems. It has been recapped, some tubes replaced, a bad socket and so on. When i power the radio up I get nothing at all out of it and cannot seem to figure out why ? I have good B+voltage, audio transformer is good. Can anyone point a beginner in a good direction ?
Thanks,
Mark
Thanks,
Mark
Mark H- New Member
- Number of posts : 5
Registration date : 2011-11-28
Re: Need help with a crosley 516
Does that radio use locktal tubes? If so, suspect sockets with poor connections, and, rusty tube pins. Very common problem.
Another, have you tested the tubes?
Still another, disconnect one end of ouput transformer from spkr., and, check resistance. Is speaker good? Might be around three ohms on an ohm meter.
Is voice coil on spkr. moving freely?
If frozen, that can also kill your sound.
Bill Cahill
Oh, and, welcome to the forums.
Another, have you tested the tubes?
Still another, disconnect one end of ouput transformer from spkr., and, check resistance. Is speaker good? Might be around three ohms on an ohm meter.
Is voice coil on spkr. moving freely?
If frozen, that can also kill your sound.
Bill Cahill
Oh, and, welcome to the forums.
_________________
Please also join us here; www.videokarma.org/index.php
Bill Cahill- Admin
- Number of posts : 4423
Age : 69
Registration date : 2008-03-12
Re: Need help with a crosley 516
Hi Bill and thank you for the welcome ! I have checked all the tubes and replaced as needed. Have cleaned sockets and even replaced one. I have checked the voice coil and the output transformer and they appear to be fine. I even hooked up a spare speaker to double check but still nothing....I am really stumped....any other suggestions ?
Thanks Mark
Thanks Mark
Mark H- New Member
- Number of posts : 5
Registration date : 2011-11-28
Re: Need help with a crosley 516
Check the value of your resistor to make sure they are within tolorance. Check for burned resistors or shorted caps, sometimes they can be buried so deep underneath other components that they get overlooked. Check IF coils. Make sure that the primary and secondary voltages are correct coming out of your "power" transformer. Is there any sound at all? Buzz or hum? Are all of the tubes glowing?
Dave
Dave
Motorola man- Member
- Number of posts : 370
Age : 45
Registration date : 2010-02-06
Re: Need help with a crosley 516
Hi Dave. I have replaced all the caps and gone over the power stage and it is all working well...good voltages etc. I have checked the resistors and except for one questionable candohm all are fine. All the tubes light and have been tested good. No noise at all from the speaker ???
Mark H- New Member
- Number of posts : 5
Registration date : 2011-11-28
Re: Need help with a crosley 516
I repeat above questions on spkr.
BC
BC
_________________
Please also join us here; www.videokarma.org/index.php
Bill Cahill- Admin
- Number of posts : 4423
Age : 69
Registration date : 2008-03-12
Re: Need help with a crosley 516
Hi Bill,
I disconnected the output transformer and it read 3 ohms. Also the voice coil moves freely.
I disconnected the output transformer and it read 3 ohms. Also the voice coil moves freely.
Mark H- New Member
- Number of posts : 5
Registration date : 2011-11-28
Re: Need help with a crosley 516
Did you check both the primary and secondary ?
The candelohm resistor is a serious resistor that must be checked, sometimes they open or go bad. they are usually a dropping resistor for the filaments. May have more than one tap.
The candelohm resistor is a serious resistor that must be checked, sometimes they open or go bad. they are usually a dropping resistor for the filaments. May have more than one tap.
Resistance is Futile- Member
- Number of posts : 913
Registration date : 2008-03-12
Re: Need help with a crosley 516
Yes I checked the secondary too...it was 2 ohms. I am waiting for two replacement resistors to come in to replace the candohm...but I dont think that is the cause of the trouble Im having. Thanks for all the advice !!
Mark H- New Member
- Number of posts : 5
Registration date : 2011-11-28
Re: Need help with a crosley 516
How about trying to measure for sound at the detector output using a small amplifier (signal tracer) - be careful of high voltages and couple the output using a capacitor.
rascal- New Member
- Number of posts : 6
Registration date : 2011-12-27
Re: Need help with a crosley 516
rascal wrote:How about trying to measure for sound at the detector output using a small amplifier (signal tracer) - be careful of high voltages and couple the output using a capacitor.
I second using a signal tracer. I would be lost without mine. I have a sencore am/fm analizer I use to inject the signal. I follow that signal all the way to the speaker using the signal tracer. I made my own using plans from the late 70s/early 80s in a electronic magazine. It used a simple am radio and tapped into the volume control. It had a switch with a cap that switched from rf to audio. I made one around 84 and it still works like a champ. I need to scan it or at least post the schematic. Anyway I highly suggest a signal tracer to anyone working on one.
willy3486- Member
- Number of posts : 1390
Registration date : 2011-07-02
Re: Need help with a crosley 516
Put your finger or the tip of your plugged-in solder iron on the center terminal of the volume control. You should hear a loud buzz if all is well. If no buzz, your problem is from the volume control to speaker. If buzz, your problem lies ahead of the volume control.
Wildcat445- Member
- Number of posts : 4893
Registration date : 2011-09-19
Re: Need help with a crosley 516
The volume control on this radio is at the front end, so you may have to probe a bit differently. See:
http://www.nostalgiaair.org/PagesByModel/374/M0003374.pdf
http://www.nostalgiaair.org/PagesByModel/374/M0003374.pdf
rascal- New Member
- Number of posts : 6
Registration date : 2011-12-27
Page 1 of 1
Permissions in this forum:
You cannot reply to topics in this forum
|
|