[Hallicrafters] desperately in need of SR2000 ceramic wafer

[Jim Liles]

Good evening Milton:

In order to fix the switch, the switch plates have to be hand made using AWG24 coin silver sheet and the contacts can be salvaged from either Centralabs or OAK two rivet switches.  

The new switch configuration doubles the space between contacts and will not arc.

The problem is the SR-2000 should be used with an antenna tuner to keep the SWR under 2/1 and should not be used with an output impedance under 45 ohms.  

These things only become a problem when the loading is too light which is usually caused by inadequate transmit drive.  

We can make the wafer but the next time slot is 18 months out and the switch wafer will be expensive.  I can tell you where to obtain the materials and tools if you wish to make the wafer yourself. 

Hope this helps.

Kindest regards Jim K9AXN    

-----Original Message----- 
From: Milton Valerio 
Sent: Tuesday, April 22, 2014 9:32 PM 
To: Jim Liles 
Subject: Re: [Hallicrafters] desperately in need of SR2000 ceramic wafer 


Yes!! that was exactly what happened, in 20 mts, now why that happened? antenna? dirty contacts? too much power?
the switch plate of the other side is totally melted there is no plate nor contacts, where do I can find those plates and contacts to replace?

On Tuesday, April 22, 2014 9:25 AM, Jim Liles <hallicrafterssr2000 at k9axn.com> wrote:

Good morning Milton:

The switch that you have is the original version.  All would arc over time.  They made two more changes to the switch configuration.  The attached file is of the newest configuration.  You can use the same wafer just need new contacts and switch plates.  There will be independent switch plates on both sides of the switch as seen in the photo.  The new switch configuration doubles the spacing which prevents arcing.

The arcing would occur when using the 20 meter band, destroying the 80 and 40 meter contacts.

Kindest regards Jim K9AXN   

-----Original Message----- 
From: Milton Valerio 
Sent: Tuesday, April 22, 2014 9:50 AM 
To: Jim Liles 
Subject: Re: [Hallicrafters] desperately in need of SR2000 ceramic wafer 


This is the side which is in best shape, the other side is like if someone used a torch on it, absolutely disappeared the whole thing.
On Monday, April 21, 2014 7:04 PM, Jim Liles <hallicrafterssr2000 at k9axn.com> wrote:

Send a close up and we can determine if it is reparable and if it is the “A”, “B”, or “C” design.  No point in fixing a switch that was destined to burn up.

I would guess it is the forward wafer used for 80 and 40 meter capacitor help.

I can assure you that you will not find one unless you pay homage to a very special God.  None the less they generally can be repaired. 

Kindest regards Jim K9AXN 

-----Original Message----- 
From: Milton Valerio via Hallicrafters 
Sent: Monday, April 21, 2014 4:44 PM 
To: hallicrafters at mailman.qth.net 
Subject: [Hallicrafters] desperately in need of SR2000 ceramic wafer 

Is there a way to get a replacement for a burnt ceramic wafer? will pay $100 
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