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View Full Version : I'm never, ever parting with my TR-7!!!



W1GUH
01-08-2012, 12:59 PM
Now that I've got it operating solidly & have the power situation in the car under control, and I know what I"m doing with it, I LOVE that radio in the car. It sounds so good and is so nice to tune and so stable that it's hard to imagine a better radio. Wow! Guess I got lucky with it, so far it hardly drifts at all. If I've got it tuned to ECARS at 7255.0, it may (or may not) wind up on 7254.9 after about a half hour. Not the kind of drift I'll ever complain about. And the sound!!!! OMFG!!! Pure Drake. And that includes SW BC stations with the "no filter" mod switched in. So, OK, the high end isn't quite there, but the low and mid-ranges are full and rich sounding. (I plug in into the car sound system.) Now, if only I could find good music more consistently. Sigh. Used to heard great stuff out of Radio Netherlands lots -- guess they don't do that anymore?

N8YX
01-08-2012, 02:40 PM
If I've got it tuned to ECARS at 7255.0, it may (or may not) wind up on 7254.9 after about a half hour. Not the kind of drift I'll ever complain about.
100hz/hr is what those rigs were originally spec'd for. Problem is that the drift is not consistent. Mine will drift "up", stabilize then drift "down" if the room gets a little cooler.

Needs a synthesizer, huff-puff unit or a rock in the AUX7 to stay "netted".


And the sound!!!! OMFG!!! Pure Drake. And that includes SW BC stations with the "no filter" mod switched in. So, OK, the high end isn't quite there, but the low and mid-ranges are full and rich sounding. (I plug in into the car sound system.) Now, if only I could find good music more consistently. Sigh. Used to heard great stuff out of Radio Netherlands lots -- guess they don't do that anymore?

No, but look at the upside: You can now hear Brother Stair all across your radio dial.

There is also a mod which addresses the audio frequency response curve (or as some might say, the lack thereof). You're need to pull the IF/Detector Board and replace some capacitors. 'HFN has it on his site in the "Drake Mods.txt" file.

WØTKX
01-08-2012, 03:01 PM
I feel the same way about my old Ten Tec Omni D's, Corsair, and Kenwood TS-850. Very listenable. But I bet there's a mod to make them better. I'm a fan of killing the freqs above 6K or so. Use my Tascam audio board a lot to EQ the RX sound. My Flex 3000 has an RX and TX EQ built in, and I use it.

PA5COR
01-08-2012, 03:15 PM
Radio Netherlands is not transmitting that much anymore, and more directed to the area they want to reach listeners.
We protested against the cutback, send in our support, but the cut back just went through... just 25 million cut, and in my opinion losing a lot of support and (almost) free advertising for the country.

W1GUH
01-08-2012, 04:18 PM
100hz/hr is what those rigs were originally spec'd for. Problem is that the drift is not consistent. Mine will drift "up", stabilize then drift "down" if the room gets a little cooler.

Needs a synthesizer, huff-puff unit or a rock in the AUX7 to stay "netted".



No, but look at the upside: You can now hear Brother Stair all across your radio dial.

There is also a mod which addresses the audio frequency response curve (or as some might say, the lack thereof). You're need to pull the IF/Detector Board and replace some capacitors. 'HFN has it on his site in the "Drake Mods.txt" file.

Re: Brother Stair.

I've been saved a few times because those stations will sometimes play good sounding music!

Thanks for the tip about the mods. I'll look into it. Seems I can't help but dig into it at the slightest excuse.

W1GUH
01-08-2012, 04:21 PM
'YX:


100hz/hr is what those rigs were originally spec'd for. Problem is that the drift is not consistent. Mine will drift "up", stabilize then drift "down" if the room gets a little cooler.

I shoulda been more careful how I worded that. It's not really all of 100 cycles. Could be it's gone from, say, 7255.01 to 7249.99, or something like that. Will have to put a more precise counter on it for a real measurement. In any event, I didn't notice anything til I decided to just leave it and see how much and how fast it changed.

N8YX
01-08-2012, 04:54 PM
'YX:



I shoulda been more careful how I worded that. It's not really all of 100 cycles. Could be it's gone from, say, 7255.01 to 7249.99, or something like that. Will have to put a more precise counter on it for a real measurement. In any event, I didn't notice anything til I decided to just leave it and see how much and how fast it changed.

Paul,

That's about what I see with mine, especially in the winter. Come summertime they're a little better as the house stays warmer and the internal temperatures don't fluctuate as much.

Like you, I really don't want to get rid of any of mine - but I have to downsize a bit. Two of my R7s are staying put, as they're 'FCC specials' - fitted with an IF buffer amp which is output to a rear-panel BNC. This as delivered from Drake. A friend/coworker who was an engineer on the 5 and 7-line series said they did a lot of special-order government stuff on demand. I have paperwork from the station chief of the Allegan, MI office which details their purchase of one of the receivers plus the fitment of options.

They don't have memories or FM, they drift a bit...the transceivers don't have a notch filter (but I can fix that) and the receivers don't have squelches (I did fix that). However, more people are drawn to the TR7/R7/TR5's looks than any other gear I own. And you wouldn't believe the unsolicited audio reports I've gotten while operating them. When all of my other gear has finally given up the ghost I'll drag the Drakes back out and set them up...then reminisce about the good ol' days.

W1GUH
01-08-2012, 06:09 PM
the transceivers don't have a notch filter (but I can fix that)

The one thing I miss on the transceiver. Is that on the web? I'd love to put one in.

N8YX
01-08-2012, 06:33 PM
The one thing I miss on the transceiver. Is that on the web? I'd love to put one in.

Sorta.

;)

There are a couple Euro-hams who gutted their TR7s and put the electronics into new enclosures, leaving real estate for more controls. Since the transceiver has a relatively high 2nd IF, any notch has to be audio-based. Not to fear, because we can still build a decent AF version using an MF-10:

http://www.national.com/mpf/MF/MF10.html#Overview

Fitting a control knob will be a bit more challenging. I got hold of a few of these:

http://www.surplussales.com/Images/HamEquipment/Collins/col-259-8018-030.jpg

http://www.surplussales.com/Collins/CollKWM380-2.html

and plan to modify the TR7's Mode switch to accept the concentric shaft and potentiometer assembly. The TR5 will be a bit easier, as several of its panel controls are single pot. One's getting an RF Gain control and the other gets the notch. You can use "stock" TR7 RIT/PBT controls to accomplish this.

W1GUH
01-08-2012, 08:47 PM
any notch has to be audio-based


Oh...that's something different. Already have an outboard audio notch in a vintage Autek Research unit. Correct vintage!

N8YX
01-08-2012, 09:01 PM
Oh...that's something different. Already have an outboard audio notch in a vintage Autek Research unit. Correct vintage!

The R7's 50KHz 3rd IF makes notch interaction with the receiver's AGC easy to implement. That is, an interfering signal can be removed from the passband so it won't mask a weaker, desired signal.

Same thing with any of the rigs which use a 450-500KHz last IF. Get into the MHz IF range and it becomes a bit difficult (at least, with the available technology of the day) to implement a stable notch mechanism - the oscillators will drift.

I might look into doing something with a DDS-based unit in the TR7. Perhaps use a separate AD8951 to generate the notch reference.

W1GUH
01-08-2012, 09:57 PM
The R7's 50KHz 3rd IF makes notch interaction with the receiver's AGC easy to implement. That is, an interfering signal can be removed from the passband so it won't mask a weaker, desired signal.

Same thing with any of the rigs which use a 450-500KHz last IF. Get into the MHz IF range and it becomes a bit difficult (at least, with the available technology of the day) to implement a stable notch mechanism - the oscillators will drift.

I might look into doing something with a DDS-based unit in the TR7. Perhaps use a separate AD8951 to generate the notch reference.

Ah, thanks. I see what you said now.

The obvious thing would be to implement what's in the R-7. Sounds like that doesn't work out?

N8YX
01-09-2012, 04:06 AM
The obvious thing would be to implement what's in the R-7. Sounds like that doesn't work out?
Alas, one cannot - that requires another IF board and we're out of space as it is.

W1GUH
01-09-2012, 07:22 PM
'YX:


And you wouldn't believe the unsolicited audio reports I've gotten while operating them.

Wah!!!!! Must be somthing wrong with mine. I've heard comments like that from other TR-7 users, but have yet to get my first!!! Guess I should gut it & start over. (Just kidding!)

Re: TR-7 drift...

If my TR-7 is pretty much "normal" in that department, I gotta wonder, have we been spoiled rotten by synthesizers? Yea, the readout changed "after a while", but there was no discernible change in the audio pitch...in other words, had I not been specifically watching for it, I never would have known there was drift. And this is in a mobile environment. I'm gonna bitch about that? I doubt it very much.

N8YX
01-09-2012, 09:03 PM
'YX:



Wah!!!!! Must be somthing wrong with mine. I've heard comments like that from other TR-7 users, but have yet to get my first!!! Guess I should gut it & start over. (Just kidding!)


Align the reference oscillator then adjust the VR/PBT pots for desired response

or

Remove the stock 2.3K SSB filter and replace with a Sherwood 2.8 or 3.0KHz filter.

Then use a Drake 7077 ($$$) or an Astatic 1104 ($) mic with it. They're the same mic. One says 'Drake'.


Re: TR-7 drift...

If my TR-7 is pretty much "normal" in that department, I gotta wonder, have we been spoiled rotten by synthesizers? Yea, the readout changed "after a while", but there was no discernible change in the audio pitch...in other words, had I not been specifically watching for it, I never would have known there was drift. And this is in a mobile environment. I'm gonna bitch about that? I doubt it very much.

Yes, we have. Somewhat inconsequential when operating voice, but very critical if operating data modes.

WØTKX
01-10-2012, 11:10 AM
I'm blown away with the Tuned Notch Filter (TNF) in the latest FlexRadio software. Imagine multiple notches that you can save that are frequency specific... and you can change the notch width and depth. Like wow, man. The 40 meter general band is much easier to deal with at night now, and crowded CW or digital is much easier to deal with.

I'll never forget my Q Multiplier project as a kid... it was hard to get running (I was confused) but it made a huge difference.

W1GUH
01-10-2012, 12:33 PM
Pity the TR-7 doesn't have a 455kc IF. I could put an QF-1 on it!

Or maybe figure out how to replicate the notch in an SX-100/101/111?