Saturday, January 13, 2018

Flashback: RME-45

It's been quite a couple of weeks!  On New Years Day, I had the pleasure of being interviewed by Eric, 4Z1UG, for an episode of his excellent QSO Today podcast, which subsequently "aired" on January 7.  I imagine Eric's listeners responded in one of two ways:

1 - Who's this clown?
2 - N8NM? He still owes me money!

But, seriously, it was an honor.  To look back to some of those who've been featured in past episodes, many of whom are people who've had a marked influence on me and my amateur "career", it's nothing less than humbling.

Then, this morning, I hear my friends at SolderSmoke mention me during the same segment as Jeff Damm - wow!

And then I sit down and try to figure out why the SDR-2017/18 won't do what I want it to.  Python.  I suppose it's a great language, but I don't speak it, and, after nearly a month of hacking away at it, I've determined that I need to step back and start learning it from the ground up.  I'm a slow learner, this could take a while.

But, in the meantime, enough about me; let's talk about an old receiver: the RME-45.

Why you don't combine Ambien and Ebay.

I first became aware of this model about 25 years ago, when I was purchasing another old radio from a local collector and saw one that he had in his hoard.  What a dial!  But, since I'd already given over all my cash, I didn't ask if it were for sale, just filed the information with the intent to own one some day.  That came about five years ago, when I made the mistake of combining prescription drugs and Ebay.  Drugs are bad, just say no.  I really don't know what prompted me to pull the trigger on this deal, but I did, and a week later unpacked the wreck shown above.  At least I didn't pay much for it, at least not on the initial purchase.

Oh, but that dial!

Realistically, this should have been scrapped for parts; it had a lot of parts missing (and a few added), was rusted and dented, and, worst of all, had taken a significant "whack" to the tuning shaft, which destroyed the ball-drive and damaged the multi-section tuning cap. Ouch.

So, I'm looking at this thing, wondering what the hell I'm going to do with it, when I get this brilliant idea: Let's strip it down completely and rebuild it Heathkit style.

I'll let the pictures do the talking, but a few points of interest:
  • The ball-drive dial mechanism was replaced with one from a junked Philco 38-8 chassis, surprisingly little machining was necessary.
  • I filled the extra hole in the panel with JB Weld.
  • The wrinkled finish was simulated by spraying on a coat of Rust-O-Leum textured paint, then spraying a thin, blue-grey color coat over the top of it.
  • Yeah, I painted the chassis to cover up significant mouse-pee damage.
  • I had to make a new cover panel for the gear drive out of 22 GA steel.  This was bent-up old-school, in a vise.
  • During disassembly, I took approximately 200 pictures so that I'd know how every part was installed and every wire routed.
  • Repairing bent and broken four gang variable capacitors is hard.
  • Loctal tubes are cool!
Top view of chassis "before".  It looks better in the pic than it did in person. Mice had been busy using it as a toilet.

The stripped and painted bare chassis.

Starting to come together.

A little more progress.

The crystal filter module, ready for installation.

 First received signals were of my friend Don, K8BB, who's only a couple miles from me and was booming in at 60+ over!

As it is today.  Someday, I swear I'll get to silk-screening the labels, but as one of RME's founders said when asked why the controls on a prior model weren't labeled: "If you don't know what they do, you've got no business buying one."

So, how does it work?  Truthfully, it's outstandingly mediocre.  The performance is on-par with something like an NC-57 or S-40, the only real advantage it has over those rigs is the crystal filter, which works like that on an SX-42 but isn't quite as effective.  But it's got that great dial, and the tuning rate is adequate.  This is an early production model and has the dual-rate tuning system - the center of the the tuning knob is a slow rate, the outer concentric much quicker. 

The rig's OK, but for the same kind of money (and real-estate, it's a large box!) something like an NC-183 would have been a better value. 

73!

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