Presto K-8 Disc Recorder For Parts or Restoration

Description

Presto K-8 disc recorder for parts or restoration.
Presto K-8 in “as found” condition. There is a strong musty/oil smell. The covering over the wood cabinet is worn and brittle and probably the source of the musty smell. The wood cabinet itself appears to be in good shape for its age, no sign of water damage or dry rot. The cabinet joints are strong. Some of the cabinet corner bumpers show a lot of wear. The cabinet handle outer covering is falling off, but could probably handle the weight of the unit (although I didn’t try it). The cover latches still latch, but move stiffly and can pop open by themselves.
The speaker is a nice 8″ vintage Jensen speaker that is in very good condition for its age. I didn’t see any damage to the speaker cone and the sound is as good as you would expect for this vintage speaker.
The motor switch works and the motor spins quietly and smoothly. I don’t have any experience with this type of unit, so I didn’t do any further mechanism testing.
I was curious about the amplifier, so I opened up the unit to check it out and do some quick testing. You won’t find many amplifiers  like this one with #45 triode output tubes in a push-pull configuration.
I slowly powered up the amplifier for several minutes using a variac and noted the following:
-The toggle power switch is defective. I temporarily jumpered the switch to continue testing the amp.
-I used an iPad as a signal source (going into the “radio” 1/4″ jack).
-I only increased to the voltage to 90 volts to avoid stressing the vintage components. The output, using the Presto speaker, was surprisingly strong and undistorted for an unrestored amp.
-The can capacitor closest to the choke transformer was getting hot and needs to be replaced before further use.
-No other testing was performed.
The transformers are in good condition.
All of the capacitors should be replaced before trying to use the amplifier to avoid damage to it. The resistors should probably all be replaced also, but at least checked to see that they are within tolerance.
This is a very heavy unit (50lbs) and will be carefully packaged. It will be double boxed with appropriate packaging materials to ensure it arrives undamaged from shipping.  Shipping cost is high because of it’s size/weight and because of the cost of packaging materials.
I ship using Fedex or UPS.
Purchase with confidence, the unit may be returned for a full refund (buyer pays for return shipping) if you are not completely satisfied. Please make the decision to return the unit before starting any refurbishing.
See my ebay seller feedback comments which show the accuracy of my descriptions and my care in packaging.