[R-390] dead bands (caution Evil Images Invoked [sorry])

[Flowertime01 at wmconnect.com]

Dan,

As a new owner you must be told about the killer cap in the IF deck.
Y2K 3.2.9.3 The mechanical filters are separated from plate B+ by C553.

This cap will fail and then kill your mechanical filters.

Pull your IF deck and look for this cap. If all you see is big black or 
brown plastic .01uf caps, leave your receiver off. Read about black beauties of 
death.

At least replace this cap with a new modern good quality cap. There is also 
a small electrolytic in the audio deck that leaks acid and eats stuff. The 
two plug in electrolytic power supply caps on the audio deck get old and 
leak, let power supply voltage ripple or fail with a mess. These are all easy 
fixes.

So you have some work ahead of you. No problem. It will just take time and 
care.

7 and 24 go together. 1st and 3dr on one crystal.

15 is by its lonesome.

32 does not exist. The receiver will tune to 31.999 + over run of 30 or so 
to 32.030.

But there is no real 32 on the receiver. Your Mega hertz detent is not 
adjusted well.
You can set your receiver to 32 on the Mega hertz and run the Kilohertz 
knob from end to end but you get no signals.

The thing in common is a receiver that has just been allowed to set without 
exercise. In specific the Crystal oscillator band switch and the crystals 
in the heated oven compartment. The switch changes on every Megahertz change. 
A couple of contacts have gotten dirty / oxide and do not make good enough 
contact. Or a crystal or two in the oven have oxide in the sockets. We do 
not open up the oven cover to unplug and replug the crystals in their sockets. 
It is just a one time procedure to exercise and clean up some contacts.

Find the Y2K manual on the R390 web page and down load it. r390/a.net

This text is easy to down load if you have slow dial up modem. It will take 
time but it will down load. This text is easy to read. It will not send you 
off on a Rip van Winkel 20 year sleep like the Army TM will. Lots of nice 
steps on how to get the receiver apart so you can do some cleaning and then 
alignment checking to get the receiver back to excellent operating condition.

As you think you have 32 on your receiver, you will have some mechanical 
adjustments to make. These are all in the Y2K manual. Much easier to read it 
and do it than try it from a short mail post.

Using the manual, open the crystal oven cover and check the crystals for 
seating.
This could solve some problems.
If the gear train is clean and the cam rollers well lubed and running free, 
then just use the receiver a lot as it sets. Runing the mechanical parts 
helps to clean up the contacts.

If the gear train is coated in dust from time and things are stiff. Then do 
a cleaning process before you go to just grinding crud into the gear train 
while trying to get a switch to clean up that may or may not come around 
with ease.

Your problems are not severe or hard to cure. They are all in the range of 
normal cleaning and alignment.  You could have a bad crystal or two. They do 
go bad. Good used crystals are available here from some of the Fellows. 
Post some mail and just ask for the parts you need by value. IE the 7mhz 
crystal from the second oscillator deck. You will get a response back direct to 
you and some prices that include the postage. The Fellows are nice and do not 
have minimum order limits. You will get good used parts from receivers that 
are being parted out. 

Deoxit from an electronic supply store is well liked for cleaning.
Radio Shack stuff will work (caution counter ideas on quality)

Do a search on Julian Creek Massacre and you will learn why there are parts 
available this way. Once you poke a R390/A with a fork lift much of its 
value and many of its attributes are lost.

Roger Ruszkowski AI4NI</HTML>