The Heatkit DX-40, a conversation

[Burt]

A video on an old boat anchor
http://www.youtube.com/watch?v=YcY66wIuAlk

[ka3zlr]

Ya know Burt, you really go the extra mile there OM...these videos show alot of work and effort on your part...good video clarity..Mixed well...

Maybe the Forum outta start an AV section....That'd be different...

73
Jack

[W3RSW]

Great job Burt.

Also a nice introduction to your family and younger self.

Better buy a selection of those 60, 60 and 75 watt dummy loads while you can.
A Phillips flourescent wont load up quite the same. 

Anybody ever try to load up one with RF?

[Burt]

Ya know Burt, you really go the extra mile there OM...these videos show alot of work and effort on your part...good video clarity..Mixed well...

Maybe the Forum outta start an AV section....That'd be different...

73
Jack

I really appreciate the compliments (yours and the other response)
Burt

[Opcom]

Great to see a real demonstration of tuning and loading. That's half the fun of operating.

[AJ1G]

My first TX in 1966-67 novice days was a DX-40.  Later traded it  for a 35 mm SLR camera to the kid across the street, Glenn , now NY4NC, who frequents this list on occasion.  How ya doing Glenn?  It had a VF-1 that sounded pretty much like K1IOK's. Ended up using a command set based VFO after I got my general.

About 15 years ago, I acquired another DX-40 and VF-1 from  the estate of a co-worker's Dad.  They are both in mint condition and work much better in terms of chirp and drift.  No chirp if you don't key the VFO, and lots of drift and instability was found to be due to loose windings on the VFO tank coils, especially the low frequency coil with the 1.8 Mc fundamental.  A little coil dope settled things down remarkably.  I would bet a lot of the VF-1s out there suffer from this problem.  The first few turns on the grid end of the LF tank coil were flopping around on the VF-1 from the estate.

[W1EUJ]

I bought this set - the DX-40 AND VF-1. Because of some recent changes, I won't be going back to school as soon as I thought, so i have the time available during the night.

Dunno if it's a Cape thing, but didn't get the usual dime-tour and hour chat about radio and life like I usually do when I buy from the AM crowd. I may have arrived when a football game was on, however.

Anyway, I brought them home and opened them up. Seemed like the DX-40 had been dropped in the past, bending and twisting the chassis. The VF-1, as you saw in the video, chirps like a chicken and was corroded inside. So, as the two radios are so simple, and the parts count small, I made a decision to do what I ususally don't in a restoration.

I rekitted both of them - completely. Even got the wire harness out in one piece without clipping wires. Used ALL of my fat solder wick doing it. I clipped the resistors, capacitors, and took care in removing the hard-to-find parts like the chokes and such without clipping. Spent an entire Sunday evening both watching Ramsay's Kitchen Nightmares on Youtube, and cleaning up the parts I removed from the radio.

In kit form, I can restore/replace each part individually, and mods can be done during reconstruction (after several successful restorations recently, I feel confident in doing this). Boy, this is going to be fun, putting together a kit radio just like back in the day.

When I get home tonight, I'll take some photos of the rekitted radio and post them up.

Mods for the DX-40: Audio Improvements, PTT
Mods for the VF-1: Solid State Oscillator and Buffer, chokes on output coax shield and power lines

Open to suggestions and ideas. This is a fun little winter project, while I wait for parts to upgrade my HW-101.