HW-101 Heterodyne osc. coils, 2 slugs?

[Kenneth G. Gordon]

On 3 Jul 2006 at 3:13, John D wrote:

> Trying to go through alignment of my HW-101. There are 2 slugs in some
> of my het. osc coils. The manual doesn't say anything about adjusting
> 2 slugs. Is there anything special about I should know about adjusting
> the 2 slugs?

Yes. 5 of the coils are adjusted from the BOTTOM of the rig, and 3 
are adjusted from the TOP of the rig. There are a total of 5 
separate heterodyne oscillator coils forms, but 3 of those coil forms 
have two coils on them, and thus those three coil forms have two 
slugs.

You adjust the 3.5, 14, and 28.5 Mhz coils from the top, and the 
rest from the bottom.

Also, when adjusting the various heterodyne oscillator coils, you 
must tune them for a peak from the side that changes the voltmeter 
reading most slowly. I.e., when you adjust the slug in ONE 
direction, the voltmeter reading will change rapidly, whereas when 
you adjust it in the OTHER direction the voltmeter reading will 
change more slowly. The "more slowly" side is the correct one.

You should adjust those coils so that the voltages at the test point 
are all as identical as you can make them. The books says that 
voltages from -0.5 to -2 VDC is correct, but I set them all equal. 
Usually to -2 VDC, but in any case, not less than -1.5 VDC. 

>   The 29.5 osc seems to be dead. I can't see any reason to think it's
>   anything but a bad crystal. The solder condition indicates that
>   somebody had it out or resoldered it and may have even opened the
>   case. John

Yes. You just better get a new crystal. 

Ken W7EKB

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