[Boatanchors] RME-45 Tips

Wed Mar 22 13:17:27 EDT 2017

Thank you, Dave. That is extremely helpful. I am in the middle of one now, and I'll report back when I'm done. Here are a couple of things:
1. You are right about the bandswitch. When I was taking the chassis out of the cabinet, my thumb brushed (I mean brushed) against the wafer standby switch, and it disintegrated. The moral of the story: be extremely careful when you or your hands or your thumb are anywhere near one of the wafer switches.
2. This thing is full of Micamolds of the usually low quality. I'm wondering if RME got a good deal on them from a military contractor who had tons of surplus ones on hand. 
3. Even with the set only half recapped, it is really impressive on the higher bands. 
4. I don't have the matching speaker, but an 8-ohm speaker works fine and gives plenty of volume.
5. I'm removing a few modifications by the prior owner. Nothing too difficult. 
            Joe Connor

    On Tuesday, March 21, 2017 10:51 PM, Bob Groh <bob.groh at gmail.com> wrote:

 Thank you for the list!  I've got a RME-45 on the restore list and this
will come in very handy when the radio makes it's way to the bench.

73
Bob Groh, WA2CKY

On Tue, Mar 21, 2017 at 6:40 PM, David Stinson <arc5 at ix.netcom.com> wrote:

> One of our members wrote me about his RME-45
> project, asking about things to look at.
> I'm copying this here for general information
> and in hopes others who have revived an RME-45
> can help him with "hints and kinks."
> 73 Dave S.
> --------------------------
>
> 1. Did you find a way to get at the caps and resistors around the
> converter socket (7J7). Looking at it quickly, they look completely
> inaccessible.
>
> Most of the cap changes were done when I got
> this rig. There were some errors I had to fix.
> Photos of 7J7 base:
> https://goo.gl/photos/RrYBwdNKuVqfH8r6A
> https://goo.gl/photos/vCeKJ5Xgf43UAsNE9
>
> At the base of that tube, I replaced one cap.
> The other and resistors were still good.
> I pulled the BFO shaft and used a thin
> iron for the work.
>
> 2. Do you have any helpful hints?
> Get the correct manual for your version of
> the set. It's way helpful.
>
> Carefully go inch-by-inch, top and bottom
> and address every ground point you can
> find. Give screws a little "tweak." Make
> sure solder joints are good. Yes; it's very
> tedious and if you do it right, it will take
> a day at least. And it will pay you
> excellent dividends. As time goes on,
> I am finding more and more Hi-Z ground
> points in boatanchors that cause baskets
> full of problems.
>
> Do not attempt to un-solder anything from
> the band switch. I promise- you will break
> it and you will be unhappy with your new
> "parts" radio.  Clip the leads and solder to them.
>
> As-designed, the B+ is way too high. This
> one was like 360 Volts IIRC. It caused an
> insulation failure in a RCA jack in the middle of
> the chassis that had B+ on it.
> Photo:
> https://goo.gl/photos/N9GjucLJBQzGc7MX8
> I removed the wire since I didn't use the jack.
> But there's more phonolic in the set with B+
> on it. My solution was to remove one side
> of the B+ winding from the 80 rectifier and
> tie the two 80 plates together, changing
> it from a full-wave to a half-wave rectifier.
> This dropped the B+ to about 225 Volts.
> The transformer seems happy with it.
> Set performance did not suffer and no
> noticable hum in the audio.
>
> The audio volume knob is also the "noise
> blanker" control. You pull and push
> the knob to operate the Noise Blanker.
> The blanker actually works fairly well, though
> it does reduce audio level and narrows the
> response. But the "Normal" position is
> with the knob OUT, and I'm forevermore
> bumping the thing. I'm going to eventually
> find a way to turn that around.
>
> One of the reasons they built a pre-selector
> for the rig is that it has a bit of an image problem
> above about 12 MC. Hasn't bothered me much.
> The rig is very nice for SWLing and AM phone.
> A bit drifty on the high end but settles fairly well
> after some time.
>
> The dual tuning mechanicals have a problem with
> wear to the gears that makes tuning on the
> high bands "tricky" if you're afflicted with it,
> and I am. One of the guys said there's a
> "trick" you can do, turning one of the gears
> around to engage an un-worn area of the
> shaft. I haven't attempted that yet since
> I'm not trying to get DXCC with it, just listen
> casually to AM and SWL. I got the matching
> speaker at a local auction and like the way the
> set looks and sounds.
> https://goo.gl/photos/LbSaKwnLPHHMpjqz6
>
> I didn't have to touch the crystal filter, and
> I'm glad. I'd probably have munged it.
> It works pretty well. I was impressed.
>
> You might want to put a couple of
> diodes across the meter to protect it.
> You aren't likely to find a replacement.
>
> Align carefully according to the manual, but
> don't expect the big bandspread inner dial
> to match exactly. They almost never do,
> especially if your tuning gears have the wear
> noted above. It's never going to be an Icom.
>
> The sloooooow tuning can be a little annoying,
> but you'll appreciate it on the higher bands.
> Sensitivity on higher bands is much better
> than a Hally-Scratchers or Hammer-Head.
>
> Off/On switch being on the TONE control
> is kinda odd. TONE does work well.
>
> If it doesn't come with a fuse holder in
> the transformer primary, I'd put one there.
> Mine had one already. Haven't looked
> at the value but probably something like
> a 2 or 3 Amp slo-blow.
>
>
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