DRAKE EQUIPMENT

[W2PFY]

I haven't looked at a lot of Drake equipment but from what little I have observed, the stuff looks built very well. I think it's very close to military wiring techniques. I don't own any of their products but have been considering some transmitters as drivers for AM related gear.

What do you gents think about the line?

Which transmitters VFO is the most stable?

  

[WD8BIL]

Any of the T4X series would make very nice power VFOs, Terry.
I know Bernie W8RPW uses a T4XB, I believe, to drive his BC Rig.

[WQ9E]

Terry,

I have one of each of the 4 line from the original through the C line.  Stability is fine for all of them and although I haven't measured it I imagine the C line is a bit more stable than the original "plain 4" line.   I notice more drift with my TR-7A than with the 4 line gear.

I wouldn't quite call them military quality but build quality is very good and the only common replacement items are electrolytic caps and tubes.  Be sure to replace the bias filter caps in the AC-3 or -4 power supply even if you don't replace anything else because a failure here will result in destruction of the finals (whether or not you are in transmit mode).

Performance of the Drake 4 line is excellent and I much prefer the 4 line receivers to my Collins S line.  The controlled carrier AM produced by the 4 line is very compatible with modern SSB amplifiers.  

The plain T-4 "reciter" (no X suffix) does not have the PTO built in and can only be used in transceive mode with a 4 line receiver.  A T-4X has a built in PTO while the XB  and XC are later versions.  Depending upon your intended use, you may prefer the R-4B over the R-4C or vice versa.  A R-4C equipped with its optional crystal filters is a great QRM fighter on SSB and CW and the electronic passband tuning works very well.  A noise blanker is optional.  For strict AM use with a bit of dabbling in CW/SSB you would probably prefer the R-4B (the R-4 and R-4A are also good).  The earlier models get their selectivity via the 50 Khz "passband tuner" assembly and sound very good although the skirt selectivity is not as good as with the C line.  But for AM I prefer the sound of the earlier receivers.  The C line also has a sync line to keep the carrier oscillators in sync but a simple adjustment with the earlier gear sets up the twins for perfect transceive operation.  Any of the 4 line transmitters can be paired with any of the 4 line receivers for transceive operation.

The 4 line will cover any of the WARC bands via additional range crystals.  The T-4X will handle 4 additional range crystals, the receivers hold a larger number depending upon the receiver model.   A small cooling fan for the T-4X finals is a good idea.  If you decide to use the T-4X only as a RF driver you can reset the bias to reduce the idle current resulting in more efficient final operation.  But it must be reset before using it for SSB or AM.

[Todd, KA1KAQ]

Very nice stuff overall, Terry. In some ways even better than the vaunted Collins S-Line as Drake continued to make upgrades into the 70s utilizing newer tubes that became available. Stability shouldn't be an issue across transmitter models, depending on the amount of use and/or abuse it's seen. All models are excellent.

They are controlled carrier rigs though, and one thing you'll want to do is modify the 6AU6 modulator cathode with a 1K pot IIRC, to bump the carrier level up a bit.

Would be a good idea to add a muffin fan on top too, as sweep tubes run hot enough in SSB service. Running them in AM mode is sure to warm things up.

Have always felt the Drake gear is very undervalued compared to other gear out there. Probably because it's newer and more prevalent. It's still a very good deal overall compared to most other stuff.

[WB2EMS]

I cut my teeth on some Drake gear that my Elmer and Scoutmaster K2EAW had when I was in scouts. He'd had an NC-300 and a Valiant when I originally met him, and upgraded to a pair of Drake twins and an SB-220, and eventually a TR3 and then a TR4 in the mobile. As a young JN struggling with my KnightKit R-100 and later a BC-348, the Drakes seemed amazingly polished and smooth. I loved the feel of the tuning and how sloooow you could tune through a slopbucket signal and get it just right. (well, as right as they ever get! ) Compared to the other rigs I had used, it was heaven.

I'm surprised how well they have held up through the years. I've managed to acquire a TR4 and an R4B and T4X. The R4B is the bedside receiver these days. The T4X is about to go on the bench and get the K1JJ/WD8BIL mods that have been sounding so good out of Buddly's station lately, and I'm thinking of transplanting a 6khz wide 9 Mhz filter I've been saving for a rainy day into the TR4 so it can hear (and maybe talk) better on AM. The narrow sideband filters are too tight for decent AM reception. Since I don't have the rare noise blanker, I'm thinking of that switch to kick a pair of small relays in to switch the filter. We'll see. More projects than time.

There's still something about the feel and sound of tuning a Drake that the modern synthesized rigs just don't have. And they glow properly too!

[WD8BIL]

Kevin said:

The T4X is about to go on the bench and get the K1JJ/WD8BIL mods that have been sounding so good out of Buddly's station lately,

Thanks Kevin but I'm really trying to keep the credit where it properly resides. W2JBL and K1JJ mods used at WD8BIL are the proper cudos!

http://www.amwindow.org/tech/htm/t4.htm

[WB2EMS]

No problemo Bud. I just want mine to end up sounding as good as the one you did up. Might have some questions for you on the practical aspects when I get it on the bench on it's back.

[WA1GFZ]

I bought a chicken band trashed TR7 with blown finals and drivers back in the '80s. I've been using it for SSB ever since. I yanked the magic transistor out so it covers everything. Good for sweeping antennas. WB dynamic range 95 dB close in a bit of phase noise. Never did the PTO regulator mod to address drift. Not a big deal after it has been on for a while.

[W1RC]

My main criticism of DRAKE vacuum tube transmitter design was they chose to use sweep tubes as final amplifiers.  Back when they designed them sweeps were cheap and plentiful but not any more.

73,

MrMike

[Jim KF2SY]

My main criticism of DRAKE vacuum tube transmitter design was they chose to use sweep tubes as final amplifiers.  Back when they designed them sweeps were cheap and plentiful but not any more.

73,

MrMike

Today 6146's are going for about the same if not more $$moolah$$ than the 6JB6's or 6GJ5's.

Terry,
You can't go wrong with Drake equipment.  They generally don't drift, they are very easy to work on, they are plentiful and most models are reasonably priced or even cheap (i.e. TR4's).

web resources:
This Drake descriptive summary of mods and general Drake technical features was written by VE3EFJ and has been floating around the internet for many years.

http://www.zerobeat.net/drakelist/drakemod/drmodtoc.html

Also:
http://www.zerobeat.net/drakelist/

And WB4HFN's excellent Drake pages:
http://www.wb4hfn.com/DRAKE/DrakePageHome.htm

               '73 Jim-