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[AMPS] Band Switch Stop on Drake L-7

To: <amps@contesting.com>
Subject: [AMPS] Band Switch Stop on Drake L-7
From: Mike" <W4EF@dellroy.com (Mike)
Date: Sat, 4 Aug 2001 06:00:29 -0700
Hi Joe,

I didn't get any other replies so I took another look at the amp last night.
I turns out that I was taking the wrong approach by try to come in from
the top/bottom. The correct procedure for accessing the stop screw is
as follows:

1. Remove the top/side cover from the amp.

2. Remove the black plastic end-caps from the front panel (this will
expose the screws that hold the front panel of the amp to the chassis).

3. Remove the bandswitch, load, and tune control knobs.

4. Remove the six screws (3 on each side) that hold the front panel to 
the chassis sides.

5. Remove the front panel (there is enough service loop on the switch
wire harness to pull the panel straight out and then rotate it out of the 
way). 

6. Remove the small access cover on the bottom of the amp that covers 
the tuned input network (this cover is right under and behind the 
bandswitch knob). 

7. Remove the screw holding the tank coil to the ceramic standoff on top
of the tuned input compartment. 

8. Loosen the set screw on the brass shaft coupler connecting the bandswitch
shaft to the bandswitch knob. Remove the bandswitch knob shaft.

9. Remove the phenolic standoff on the bottom of the first bandswitch wafer 
(this
is the lower power wafer that switches the tuned input). This will allow you to
get a wrench on the coupling nut that holds the bandswitch detent assembly 
against
the back of the tuned input compartment. 

10. Remove any additional sheet metal screws that are holding the tuned input 
compartment to the bottom of the chassis. 

11. Slide the tuned input compartment off of the main bandswitch shaft. 

12. You should see a small nut (~2-56) on the face of the main bandswitch detent
assembly. This holds the 10 meter stop screw in place. Loosen the nut and 
remove 
the stop screw. 

13. Since everything is taken apart, now is a good time to install the 
additional 
capacitors in the tuned input network.

14. Put everything back together. (guess they didn't want to make this mod too 
easy). 

Hope this is helpful. 

73 de Mike, W4EF....................



----- Original Message ----- 
From: "Joe Subich, K4IK" <w8ik@subich.com>
To: "Mike" <W4EF@dellroy.com>
Sent: Monday, September 03, 2001 9:05 AM
Subject: RE: [AMPS] Band Switch Stop on Drake L-7


> 
> Mike, 
> 
> I have the same modification to make here ... please share any hints 
> you may receive!  Thanks ... 
> 
> 73, 
> 
>    ... Joe, K4IK 
> 
> 
> > -----Original Message-----
> > From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On
> > Behalf Of Mike
> > Sent: Monday, September 03, 2001 9:35 AM
> > To: AMPS
> > Subject: [AMPS] Band Switch Stop on Drake L-7
> > 
> > 
> > 
> > I started the process of adding 10 meter capability to my Drake 
> > L-7 this morning.
> > The first step, removing the low-pass filter in front of the 
> > tuned input, was quite
> > easy. The next step, removing the stop in the bandswitch looks a 
> > little tricky.
> > The stop appears to be on the detent just behind the shielded compartment
> > which contains the tuned input circuitry. Is there any easy way 
> > to access this
> > area short of disassembling and removing the tank components from 
> > the bottom
> > cover?
> > 
> > Thanks!
> > 
> > Mike, W4EF............................
> > 
> > 
> > --
> > FAQ on WWW:               http://www.contesting.com/FAQ/amps
> > Submissions:              amps@contesting.com
> > Administrative requests:  amps-REQUEST@contesting.com
> > Problems:                 owner-amps@contesting.com
> >


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