[Heathkit] HR-1680 Dead Band

[Bwana Bob]

That is a possibility. I don't remember if there are adjustable tuned 
circuits in the oscillator circuits  in the HR-1680.  You might also 
check for cold solder joints on the crystal pins. I have had 
low-activity crystals come back to life by heating the pins with a 
soldering iron.

                     73,

                     Bob WB2VUF

On 4/13/2016 9:39 AM, Ron Youvan wrote:
> Jonathan WS1K Jesse wrote:
>
>> Thanks to all who replied on and off the list.
>> The previous owner did disclose that 15 meters would work for a short
>> time and then fail.  He added that it sometimes would come back off 
>> and on.
>> I did check all of the other bands and the crystals are oscillating.
>> I put a request in to International Crystal for a quote.  There is a
>> seller on Ebay who does have the needed crystal.  I'm just a little
>> leery of getting another old crystal having the same problem of not
>> wanting to do it's job.  That's kind of why I was looking for a fix to
>> get the stubborn old one to oscillate, providing it's not wasted.
>
>   It is possible that the tuned circuit in the oscillator circuit for
> the 15 meter band is improperly tuned whether it has a tuning control
> or not.  Crystals tend to fail and stay failed, so other possibilities 
> need examined.