[HBR] 160 Meter Coil Data

[Hopperdhh at aol.com]

OK folks,

Here is my design for the 160 M coils for an HBR with the 1461-BS variable 
capacitor:

For L1 and L2:
69 1/2 turns of no. 26 on the 1 1/4 inch polystyrene forms will cover the 
entire 160 M band.  No tap, connect pins 3 and 4 together inside the coil form.  
You will need a total of about 56 pF across the coil, so a 39 pF fixed + a 50 
pF variable should do it.  I would suggest a modern sub-miniature variable 
placed way down in the form as a practical alternative to the APC which would 
probably spoil the coil's Q.  In keeping with Ted's ratios, try 23 turns for the 
primaries.

For L3:
19 1/2 turns of no. 26.  No tap -- same as above.  You will need a total of 
about 116 pF across the coil.  Use 75 pF silver mica + 50 pF variable as above. 
 Feedback would take about 13 turns, again keeping Ted's ratio.

It'll work, I tell ya!  Would the first person who tries it let me know?  
Seriously, these values should get you pretty close.  BTW tracking shouldn't be a 
problem.  The worst case error is only about 4.5 KHz.  This means that the 
signal is detuned only 4.5 KHz from the peak which is probably still on the 
peak!!

Regards,

Dan K9WEK