Fleetwood model 4068... Advice?

[electroking]

Hello again,

Well, a spark gap gizmo will indeed produce noise that can be received across the
band, but it is a crude instrument at best...

I won't start writing an essay about the theory of superheterodyne receivers right
away (but I can do it if you tell me it would help). Instead, let's determine if
the oscillator is running. When tuned to the bottom of the band (550 kHz or so),
the oscillator should be running at 995 kHz, and at the other end of the band
(1600 kHz), it should run at 2055 kHz. These figures are just 455 kHz about the
desired carrier frequency.

If you have two working AM radios in the house, you should be able to do some
testing. Just one working radio is actually needed for the test, but two will help
demonstrate the procedure. If you set one of the radios at the bottom of the
AM band, its LO will run at about 995 kHz as stated above, and if you set the second
radio around the latter frequency, you should be able to find a spot where you're
just picking up the radiation from the first radio. You have to try it to hear the
effect. Now as you increase the tuning of the 'source' radio, you can track its
radiation by also increasing the tuning of the 'observing' radio.

The trick to check your receiver is to use the same 'observing' radio as above
(it will work fine if it is a small portable unit with a speaker), placing it near the
oscillator tube (6BE6) in your Fleetwood. You should be able to crudely
determine whether the oscillator is running.

Let me know what happens next. Good evening.

P.S.: the method described, using a small AM radio as a probe, will not work for LO
frequencies above the upper limit of the probe (1600 or 1700 kHz), corresponding
to carrier frequencies of about 1150 to 1250 kHz. There is no guarantee that an
oscillator that works at a lower frequency does not quit at some point in the
frequency range.