I have an Sears silvertone console with wire recorder and phono. Model 101-831-A.
After recapping the receiver section and changing out of tolerance resistors. I powered it up on the bench.
It plays on both am & FM. My question is: How much current draw should it have on the amp meter in series with the power line cord? It is reading btwn. 850mA & 900mA on the the amp. gauge. The line voltage is set to 117 V.
This is a 12 tube unit with the following tubes
2--7C7s
2--7W7s
2--7C5s
1--7A6
1--7C6
1--7N7
1--7F8
1--6AG5
1--5U4G
Help is greatly appreciated. Thanks
Does the unit have a wattage rating?
Divide the wattage rating by 117V, see if it is .9.
Yes I found it inside the cabinet-- 215 watts. I came up with 1.837 Amps so I guess it is okay? The wire recorder is also the amplifier in this unit and I currently have it apart for repairs. would that explain the lower rating I'm getting?
Any today's computer is a power hog compared to that.
This is true. Its just that most of the radios I've done has drawn about anywhere btwn. 300mA and 750mA. I only had it on about 15 minutes and the power transformer was barely warm . So I wanted to check with some of you guys before I
unintentionally did damage.
(05-07-2016, 02:44 PM)KCMike Wrote: [ -> ]Yes I found it inside the cabinet-- 215 watts. I came up with 1.837 Amps so I guess it is okay? The wire recorder is also the amplifier in this unit and I currently have it apart for repairs. would that explain the lower rating I'm getting?
Yes. You would have to run all of the devices at the same time to come up to the rated wattage. Sounds like you are about right.
Now if you want to be safe you can check the plate dissipation on the driver and output tubes against the RCA spec. These are the places where a bad cap or wrong screen voltage can make a real difference but you'll see it in the plate dissipation or voltage on the pins.
Thank you. I'm going to do alignment on it tomorrow and will get the tube specs and check that first. I did replace all the caps and there was plenty of them. 20 I think.
Took some voltage readings on the rectifier tube today and stopped after getting these readings.
pin 8 & 2 307 volts DC schem. calls for 375V
pin 4 & 6 284 volts AC Schem has no volt rating on 2 & 4 pin. this is the secondary of the switch side of transformer.
I don't know if the wire recorder / amplifier has to be in the circuit or not for correct volt readings. On schematic you see that amplifier has its own rectifier. I'm concerned about the high AC readings and what I should check.
Here is the schematic of the radio and amplifier kind of blurry but you can see the pin out of the 5U4G tube.
Any ideas what I should check next? Thanks
https://www.dropbox.com/home/silvertone%...ematic.pdf
< 307 volts DC schem. calls for 375V
Could have a weak 5U4. See it in tv's a lot.
If you measure from p4 to p6 on the 5U4 should see about 800vac.
Terry
Thanks Terry. I was measuring the 5U4G tube 4&6 pin to chassis. I will test the tube again, it did show good when I tested it about 3 weeks ago when first started on this project. I don't remember the exact readings. I also have other 5U4Gs I can try. I did get the voltage readings on the out put tubes and the were within 5 volts of schem. using a fluke multi range DMM.
kcmike
nice job I like it
sam
Thanks Sam. Now to get some strong backs to move it upstairs to the den.
(11-15-2016, 08:22 PM)KCMike Wrote: [ -> ]Thanks Sam. Now to get some strong backs to move it upstairs to the den.
It is nice that somebody is saving these. Their size limits most of us.
And, to that point, some of my display is upstairs. I have to assemble the radio on-site rather than try to get the whole thing up the steps.
Recently I bought one of these Silvertone consoles at an auction close out. Did you ever find a schematic?