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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">On 18 Apr 2016 at 23:28, Glen Zook wrote:</span></font></div>
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<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> You are reading the manual incorrectly! What it means by the dual tuning</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> capacitor is there are 2-sections to the capacitor and there is a separate</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> bandspread capacitor. </span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Glen: the manual says nothing about a dual-tuning capacitor. Here are the exact words from
page 3, 2nd paragraph, of the original Heathkit AR-3 manual:</span></font></div>
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</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">"Four frequency bands, IN CONJUNCTION WITH DIRECT PLANETARY DRIVE, provide
continuous tuning from 550 kc to 30 mc."</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">The next sentence reads as follows: "No communications type receiver would be complete
without bandspread." Then: "The AR-3 has been equipped with electrical bandspread that
operates at optimum efficiency on all frequency ranges."</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">So how do you interpret the bolded section above? In addition, why is there a 1/4" section of
the main tuning capacitor shaft to which the knob is attached, and which then fits inside the
larger section of the shaft which is then connected to dial-pulley and the rotor plates?
Lastly, I own several NOS BC band tuning capacitors which look identical to this capacitor
(except for capacitance values), and which ARE "verniers".</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> The dial pulley is attached directly to a 1/4th inch diameter shaft</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Not so: the dial pulley is connected to the larger shaft which is connected to the rotor.</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> that is directly attached to the main tuning capacitor rotor. </span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Not so. Look closer. The 1/4 inch shaft fits INSIDE the larger shaft which connects to the
rotor. The 1/4 inch shaft does not connect directly to the rotor, nor to the dial-pulley. At least
this is the case in all three of the AR-3s I have here.</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> There is no reducing mechanism, of any type, in both the AR-2 and AR-3. At</span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt">> least in both of my receivers. </span></font></div>
<div align="left"><font face="Arial" color="#0000ff" size="2"><span style=" font-size:10pt"><br />
</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Well, I don't know about the AR-2 since I don't own one, but I am almost certain that the AR-3 DOES have one, but at this late date, it is frozen solid. I am equally certain that all other
AR-3s which have original tuning caps have the simple vernier mechanism but are all frozen
solid.</span></font></div>
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</span></font></div>
<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Anyway, I aim to find out.</span></font></div>
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<div align="left"><font face="Arial" size="2"><span style=" font-size:10pt">Ken W7EKB</span></font></div>
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