[R-390] Posted R390A Problems

[Ben Loper]

I can't speak for everyone, but I've had my radios in bits and pieces and I knew every little detail, but I forget and sometimes I need a nudge.  I'm rebuilding a 75 a-2 and as I slowly pull it apart things come back to me.  I'm sure as I make progress I'll quit asking and start telling.

Sent from my iPhone

On Feb 1, 2011, at 14:06, Perry Sandeen <sandeenpa at yahoo.com> wrote:

> Good People,
> 
> Over the last six months or so I’ve become concerned about some of the questions posted. 
> 
> Not to beat a dead horse again any more than necessary HOWEVER:
> 
> 1.  Reality Check.  These radios are not modern rice-boxes.  They take a certain amount of maintenance depending on many variables.  There is no free lunch.  We either cut bait or fish as we are on our own.  There is no nearby Radio-TV repair shop.
> 
> 2. Knowledge.  Not everybody of the list is an Eddie Einstein nor needs to be.  If one downloads and READS the Y2KR3 manual, the many tutorials of Roger in chapter 9 will answer many, many of the questions posted here.  The same is to be said for the “Pearls” and copies of the “TM” series of manuals.   If one Reads The Fine Manual(s) - enlightenment will follow.  Remember the net is not a guaranteed library.  It can disappear or be shut off without warning.
> 
> 3.  Spare Parts.  One should have at least a complete set of known good tubes.  I buy them on epay when there are four or more NOS of one type as the postage is almost the same as for one.  Alternatively buy a set of tubes from one of the better dealers on the net and then test them in you receiver while it’s still working OK.  Check the age of the plug in electrolytic filters anything older than 10 years should be replaces.  Get Deoxit and read previous posts.
> 
> 4.  Test equipment.   Get a DVM.  One can buy a 3.5 digit new all day for way less than $50.   A used working VTVM found all day on epay for way less than $50 shipped.  Make a tube adapter as shown in The Fine Manual and make some general readings BEFORE one needs to.  This takes time but is not rocket science.  Also have several one or two foot lengths of 2 X 4s for support on side or bottom positions while testing.  Acquire or make simple crystal calibrator, such as found in the ARRL handbook or old copies of Ham Radio or QST.  This will tell you what bands are good, give an approximation of quality and can be used for some calibration.
> 
> 5.  Due diligence and preventive maintenance.  Look, listen, sniff and move.   While operating look listen and sniff on both top and bottom for anything unusual.  Gently move tubes and plug connectors looking for a change of operating characteristics.
> 
> We all start at zero and work our way up.  We’re all willing to help.  However there is a personal responsibility here of each owner to do their fair share of the “heavy lifting”.
> 
> Regards,
> 
> Perrier
> 
> 
> 
> 
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