SB-102 - more troubles

[Bob Burns]

Hi Brian
 
Well done so far. These rigs are forty years old now so it is not  
surprising that some problems are surfacing.
 
I would sparingly apply some switch cleaner to all of the switch contacts,  
move them back and forth a few times and then remove as much of the cleaner 
as  possible with a cotton wool bud or similar. I use Electrolube here in 
the UK but  I guess that you have an equivalent in your part of the world.
 
Your LMO frequncy wobble problem is almost certainly due to the grease on  
the variable capacitor having dried up. I have had this problem on an SB101 
and  the cure is relatively simple. The quick fix is just to apply a little 
switch  cleaner to the bearings and sliding contacts on the tuning capacitor 
and it will  thin out the remaining grease. However, the long term fix is 
to remove the LMO  and properly clean and re-grease the variable capacitor. 
This is a fiddly job  but not technically difficult - just needs some 
patience and the right  tools.
 
When you have finished that task and reassembled the LMO you will need to  
check the calibration and align the dial on the drive shaft.
 
While you are at it, check the preselector and PA variable capacitors as  
well.
 
73

Bob 

G3OOU
G-QRP  6907
Joint site with Crystal Palace Radio & Electronics Club: _www.g3oou.co.uk_ 
(http://www.g3oou.co.uk/) 
My technical site: _http://www.qsl.net/g3oou/_ (http://www.qsl.net/g3oou/) 

-----------------------------------------------------------
Products bought, sold or traded here is the responsibility of the
parties involved.  This list and the City of Tempe are not responsible
for losses or misrepresentations of any kind.  Buyer beware!

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.aspx?list=HEATH
To post - HEATH at LISTS.TEMPE.GOV
Archives - http://lists.tempe.gov/archives/HEATH.html