[ARC5] The HP-606 saga. (Was screw removal, but now it's different ...)

[Richard Knoppow]

----- Original Message ----- 
From: "Leslie Smith" <vk2bcu at operamail.com>
To: "Wayne Eleazer" <releazer at earthlink.net>
Cc: "ARC-5 List" <arc5 at mailman.qth.net>
Sent: Friday, March 02, 2012 6:48 AM
Subject: [ARC5] The HP-606 saga. (Was screw removal,but now 
it's different ...)

    Cycling is not necessary and does no good. If a cap is 
bad it can't be reformed in place but should be run up on an 
external supply. The caps are probably OK anyway. Just fire 
it up and let it run.
    A short when changing bands can come from a lot of 
things. However, the arrangement of the band switch is such 
that the HV is cut off while the switch is in mid position. 
You will have to open the thing and find out what got fried. 
You can't trouble shoot unless you do that.
    Output level accuracy depends on the calibration of the 
metering circuit, there is a procedure in the handbook. The 
606A book will work for the B. You need an accurate RF 
voltmeter. The meter and output system is calibrated when 
terminated into a 50 ohm load.
    The 3 volt output increases the voltage on the amplifier 
and is meant for short time use without modulation. Short 
time means several minutes anyway, its not going to blow up 
in a few seconds. Mainly it shortens the life of the 
amplifier tubes. Its necessary for some measurements, for 
instance for driving a bridge connected to an antenna where 
external pickup is high.
    Normal operation should meet about half the spec, 
frequency calibration is excellent when the set is adjusted 
properly. Output accuracy is dependent on the attenuator, if 
its off one or more levels its probably due to a fried 
resistor in the attenuator. They can be repaired.
    The 606A and B are outstanding generators with excellent 
modulation capability and very low phase noise.  The B 
version was designed to be used with an external 
synchronizer but does not have to be.
    If you need more help I suggest posting to the 
Agilent/Hewlett-Packard mailing list.
    I worked on a lot of 606's when I worked for 
Hewlett-Packard but it was a long time ago and my memory of 
them is not that good. I do remember a few tricks for 
aligning them but not nearly as much as I do for other 
stuff. I think we simply did not see many of them.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com