Offered: One Hickok 539-B vacuum tube tester for parts or restoration. This one is missing its case. No bottom case or lid is available. The previous owner said that the tester was stored in a damp environment and that the case was \"completely gone\". SO. If you happen to have an extra 539 case laying around then here you go. OR you can make one. This tester looks complete. The only problem I can see with it is that one of the PC boards has broken off at its screw down point (photo attached to the listing) I don\'t think this is going to be a problem. Briefly tested. Line level meter works, but reads high. Turning the line level pot turns and moves the line level meter even higher pegging it out. Bias circuit meter does not read. Turning the pot makes no difference. All switches and controls appear to work otherwise. Set up for testing a 6L6 reveals that the GM circuit works and will actually give a reading even without the bias set. The GM meter moves freely and does not appear to drag at any point. Shorts circuit shows no reading. Lamp may be out. Roll chart turns freely. Note that there are additional manual reprints incuded. Fixable? I would imagine so. Having a good GM meter is a plus as these are expensive. AC line meter certainly works. Bias meter? I will give an ohm meter reading to see if its open and report here later.

On Jun-27-16 at 10:23:54 PDT, seller added the following information:

Bias meter checked. Shows a DCR of 99 ohms in circuit, which I suspect is too high, but I don\'t have another one around here to confirm it as good or bad.