[R-390] New Project (More Questions)

[Mark Huss]

On nr 3. Wait until you recap, if you are, and the alignment. One of the 
preselector Racks (First IF Tuning) is 2-4 Mc, I believe.(it is bedtime, 
and i did not look in the manual).

As far as test equipment goes, you need a meter, a signal generator with 
a GOOD Attenuator, and a VTVM. You also need the spline wrench, and a 
very long #2 Phillips (12-18 inch). You need tube pullers ( the chinese 
finger puzzle type is good), and a 7 and 9 pin tube extender. What I 
mean by a Good attenuator, the 390 and the 390A are sensitive as can be. 
Most inexpensive signal generators are a real pain to use on them 
because the leakage will make it impossible to get good S+N/N. URM-25's 
are barely acceptable.

A scope and a sweep generator (only has to sweep about +-8 kHz), and 
perhaps a 600 ohm audio power meter are all the optional equipment you 
need. A freq counter for the signal generator is handy. And an 
autotransformer can come in handy as well to drop the 120VAC to 110 VAC 
(keeps the B+ down if you have the rectifier mod).

Carole White-Connor wrote:
> Today, I redid the filter caps, replaced the "exploding" cap and adjusted the IF
> gain. The set is performing nicely, but I have a few more questions:
>
> 1. The AF deck had two 3223 tubes in place of the 5814As. Is that an acceptable
> substitute? I replaced them with NOS 5814s.
>
> 2. Some of the caps are Westcaps. Are these like the usually reliable Vitamin Qs or
> like the unreliable brown/black beauties?
>
> 3. The two bands that are relatively weak are 2-3 mhz and 3-4 mhz. Any ideas on
> where I should look for the problem?
>
> 4. WHen I switch from AGC to MGC, I don't get the jump in signal strength I expect.
> It doesn't overload on MGC, even on relatively strong stations. Is that normal? If
> not, what should I be looking at?
>
> Again, thanks for all your help. There is nothing better than advice from guys who
> have been under the hood of these sets.
>
> Joe Connor
>
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