[Boatanchors] Fw: HRO Alignment of Plug-In Coilsets

[Olaf Madsen]

 > Subject: HRO Alignment of Plug-In Coilsets
>
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>>I am working on an HRO-7,trying to make the alignment on the various 
>>plug-in coilsets.----HRO-5,or any of the other HRO's also use these 
>>coilsets.
>>
>> The sensitivity varies greatly over the tuning range,particularly for the 
>> General Coverage Ranges (say 3.5 to 7.3 Mc for the ''C'' set )
>>
>> The procedure for alignment described in the instruction manual allows 
>> for adjustment at a HIGH frequency point of the range (7.3Mc for the 
>> ''C'' set ) by the trimmers which are accessable at the front of the 
>> coilsets from the inside of the receiver.
>>
>> Any alignment to the LOW frequency end must be made by changing the 
>> Inductance of the coils from the back of the coilset---however---there is 
>> NO ACCESS to them ,except when the coilset is OUT of the receiver..---the 
>> same goes for the Padding trimmers,they cannot be reached while the coil 
>> set is plugged in.
>>
>> In the words of the manual : ''The original alingment was ("is'') 
>> accomplished by the use of precision,crystal -controlled test 
>> oscillators.---No realignment should be attempted,'' etc etc.
>>
>> What's  a ''boanchor ham'' to do with a 50 odd year piece of gear that 
>> needs some TLC.--What do you say you old  guys from ''National 
>> Company''---Any advice ????---or references.
>>
>> Tnx fr any help --73 de Olaf,KF4TP---
>>
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