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Re: T4XC Power Output?

 

Jay I'd say all is normal or close to it other than 3550. Now was that into a 50 ohm? nonrestrictive load?

Nothing to be concerned about actually no one will tell the difference on the receive end.

Tim

WB8UHZ

On Monday, January 20, 2025 at 07:42:10 PM EST, Jay W6CJ via groups.io <lastradioman@...> wrote:


Group,
While making a cheat sheet for pre-tuning my T4XC (see attached excel doc), I noticed low power out on some frequencies - especially 3550 Khz.? ?What is normal power output on the traditional & WARC bands?

A W4 wattmeter was used.

73 from the LA dystopia? ? ??
Jay
W6CJ



T4XC Power Output?

 

Group,
While making a cheat sheet for pre-tuning my T4XC (see attached excel doc), I noticed low power out on some frequencies - especially 3550 Khz.? ?What is normal power output on the traditional & WARC bands?

A W4 wattmeter was used.

73 from the LA dystopia? ? ??
Jay
W6CJ



Re: TR-4C Problems with 28.0 and 28.5 bands

 

This is a long-shot.

Try adjusting T1.

Steve Wedge, W1ES

Time flies like an arrow.? Fruit flies like a banana.

Sent with secure email.

On Monday, January 20th, 2025 at 3:40 PM, Dave KD5FX via groups.io <land.dave@...> wrote:

Yes, I have tried switching the Xtals all around. I first put the 28.0 Xtal in the 29.1 slot and got nothing, no receive. I then put the 28.5 Xtal in 29.1 and got the same, nothing. Then I put the 29.1 Xtal (which works OK when in the 29.1 slot) in the 28.0 and 28.5 slots and got nothing. So that was strange, the problem didn't move, still no receive on 28.0 and 28.5.?
A friend suggest using my SDR to listen to the V1 oscillator freq and see what I was getting. So I made a sampler probe with a short piece of coax and a small coil of wire and only needed to get it close to V1 to get a strong signal.? I started with 7.0 band which is 21.5 MHz and the 21 band which is 35.5 MHz and got good strong signals on the SDR with both bands. On 29.1 I am getting a strong signal at 43.6 MHz but 28.5 (43.0 MHz) and 28.0 (42.5) had nothing. So I set it to 28.5 band and tweaked the L5 control I was soon able to get a signal near the proper 43.0 MHz but not exactly, it would be just below that and then as I turned it just a bit more it would skip over and be above 43.0 by a few KHz. I could never get it right on 43.0. However, when I hooked the Drake back up to an outside antenna I am now getting SSB signals across that 28.5 band! But the dial is off by about 20 KHz. So that's better than nothing on that band! 29.1 band is still working normally and 28.0 band is not working at all, I could never get it to tune up and oscillate. Perhaps that Xtal is bad.?
I temped to just quit there, it's working except for 28.0 band.?
73, Dave KD5FX
?


Re: TR-4C Problems with 28.0 and 28.5 bands

 

Yes, I have tried switching the Xtals all around. I first put the 28.0 Xtal in the 29.1 slot and got nothing, no receive. I then put the 28.5 Xtal in 29.1 and got the same, nothing. Then I put the 29.1 Xtal (which works OK when in the 29.1 slot) in the 28.0 and 28.5 slots and got nothing. So that was strange, the problem didn't move, still no receive on 28.0 and 28.5.?
A friend suggest using my SDR to listen to the V1 oscillator freq and see what I was getting. So I made a sampler probe with a short piece of coax and a small coil of wire and only needed to get it close to V1 to get a strong signal.? I started with 7.0 band which is 21.5 MHz and the 21 band which is 35.5 MHz and got good strong signals on the SDR with both bands. On 29.1 I am getting a strong signal at 43.6 MHz but 28.5 (43.0 MHz) and 28.0 (42.5) had nothing. So I set it to 28.5 band and tweaked the L5 control I was soon able to get a signal near the proper 43.0 MHz but not exactly, it would be just below that and then as I turned it just a bit more it would skip over and be above 43.0 by a few KHz. I could never get it right on 43.0. However, when I hooked the Drake back up to an outside antenna I am now getting SSB signals across that 28.5 band! But the dial is off by about 20 KHz. So that's better than nothing on that band! 29.1 band is still working normally and 28.0 band is not working at all, I could never get it to tune up and oscillate. Perhaps that Xtal is bad.?
I temped to just quit there, it's working except for 28.0 band.?
73, Dave KD5FX
?


Re: The Hum-Less 2B

 

Good point. I¡¯d find a way of using the slots.?

I don¡¯t mind using the Hayseed kits for sets that I¡¯m keeping. I am, however, beginning to use my Sprague TO-6 to test the caps after I unhook the wires. I have found that most of the receivers and earlier TR-4¡¯s have can caps in them that still pass testing by a comfortable margin.?

The most troublesome can caps I have found are on the TR-4C(any) and the T-4(any). Any TR-4C sets that cross my bench will get new caps if they don¡¯t have them replaced already.?

Steve Wedge, W1ES

Time flies like an arrow. Fruit flies like a banana.


Sent from for iOS


On Mon, Jan 20, 2025 at 08:46, John K5MO via groups.io <johnk5mo@...> wrote:
I'm planning to use a bit of silicone and a soldered ground.

John K5MO

On Mon, Jan 20, 2025 at 7:59?AM Mike W5RKL via <mikew5rkl= [email protected]> wrote:
I saw that small PC board with individual radial lead capacitor kit available on eBay
but after studying the PC board it appeared that 2 holes needed to be drilled in the
2B chassis. While I'm sure the small PC board cap kit works after installing it on the 2B
chassis, having to drill 2 holes in the chassis to mount the small PC board was not
something I was willing to do. I used the hayseedhamfest Drake 2B capacitor kit that
worked very well and didn't require drilling holes in the chassis.
?
73
Mike W5RKL
?


Re: 4-Line Crystals for 10M

 

That was me and thank you!

Bill N1WL

?
?

William Losefsky?

?????????



On Monday, January 20, 2025 at 12:04:34 AM EST, n4buq <n4buq@...> wrote:


I think someone was having problems with two of the 10M bands with a 4-line rig recently.? I happened to see these and thought I'd pass the ad along:



Thanks,
Barry - N4BUQ






Re: The Hum-Less 2B

 

I'm planning to use a bit of silicone and a soldered ground.

John K5MO


On Mon, Jan 20, 2025 at 7:59?AM Mike W5RKL via <mikew5rkl=[email protected]> wrote:
I saw that small PC board with individual radial lead capacitor kit available on eBay
but after studying the PC board it appeared that 2 holes needed to be drilled in the
2B chassis. While I'm sure the small PC board cap kit works after installing it on the 2B
chassis, having to drill 2 holes in the chassis to mount the small PC board was not
something I was willing to do. I used the hayseedhamfest Drake 2B capacitor kit that
worked very well and didn't require drilling holes in the chassis.
?
73
Mike W5RKL
?


Re: The Hum-Less 2B

Mike W5RKL
 

I saw that small PC board with individual radial lead capacitor kit available on eBay
but after studying the PC board it appeared that 2 holes needed to be drilled in the
2B chassis. While I'm sure the small PC board cap kit works after installing it on the 2B
chassis, having to drill 2 holes in the chassis to mount the small PC board was not
something I was willing to do. I used the hayseedhamfest Drake 2B capacitor kit that
worked very well and didn't require drilling holes in the chassis.
?
73
Mike W5RKL
?


Re: Using an R7A with a TR7A

 

Thanks to all for the documents!

73,

Steve Wedge, W1ES

Time flies like an arrow. Fruit flies like a banana.


Sent from for iOS


On Mon, Jan 20, 2025 at 03:07, Karl du Roi, DK7AL <dk7al@...> wrote:
Steve,

have you already seen and checked this piece of information regarding
building an interconnection cable between Drake TR7 and R7:

https://www.dl7maj.de/TR7-R7-cable.pdf

Best regards.

Karl, DK7AL

Am 19.01.25 um 23:13 schrieb Steve Wedge, W1ES/4 via groups.io:
> Folks ¡ª
>
> I have someone asking me to get their R7 to work with a TR7. I just want to make sure that the connectors and cables are still obtainable.
>
> Any insights into this?
>
> Steve Wedge, W1ES
>
> Time flies like an arrow. Fruit flies like a banana.
>
> Sent from [Proton Mail](https://proton.me/mail/home) for iOS
>
>
>
>







Re: Drake repair service

 

On Sun, Jan 19, 2025 at 03:41 PM, Jim Shorney wrote:
>Interesting video but his glitch diode configuration has me puzzled. He complains (rightly so) that the B- was returned to the chassis but connects a reversed diode pair in which one of the diodes returns the B- to the >chassis? The glitch diode implementations I have seen use only a reverse biased diode from B- to chassis ground. Am I missing something?
With the 2nd diode installed (rvs connected pair).....the pair? ensures the B-? ?can't wander more than? +/-? .7 vdc? ?from chassis potential.? ?In the old days, something like a 10 ohm resistor from B- to chassis? would accomplish the same thing.? The concept in both cases was to float the B- from chassis potential just enough..... to be able to measure plate and grid current.? The issue with the 10 ohm resistor is if the anode arcs to the grid, or chassis, the fault current path is up from the chassis, through the resistor.... and back to the B- of the filter caps..... completing the loop.....and of course the resistor grenades.?

With any anode to grid arc, or B+ to chassis arc, only one diode is required ( UN-banded end? facing the chassis).? ?I install the 2nd diode just to ensure the B-? can never wander more than +/- .7 vdc from the chassis.

With any GG amp that has a grid over current circuit in it, it will not function correctly, since the 2nd diode is electrically in parallel with the? typ small value resistor used in the grid over current assy.... ( typ wired in series with the negative end of grid meter / grid shunt..... and chassis).? ?The V drop across the low value resistor is now in parallel with the 2nd diode, biasing the 2nd diode on.? Then grid current flows? up from the chassis....and through the 2nd diode........ instead of up through from the chassis.... and through the small value grid sense resistor...... which results in low or no? grid current readings, even though plate current reads normal, and PO is normal.??

That's why only one diode is used on ameritron amps that have the grid over current scheme installed.? ?In older books, you will see the rvs connected pair of diodes across? both the grid and plate current meter..... and that scheme still works......? ?with or without the grid overcurrent sense circuit installed.?

In the L4B in question, the customer paid for packing and shipping to Ron, plus a helluva lot of money up front, only to be told it was unrepairable...and Ron wanted to keep the amp? and the HV supply....and the money.? Customer was told when the plate xfmr heats up, it shorts out.? Nothing wrong with the plate xfmr.? It's all fixed now.....plus the customer got his money back from Ron.? ? Dunno, but Ron might be starting to lose it.? ?And that could result in a dangerous scenario, esp with +2650vdc? involved.?


Re: Using an R7A with a TR7A

 

Steve,

have you already seen and checked this piece of information regarding building an interconnection cable between Drake TR7 and R7:



Best regards.

Karl, DK7AL

Am 19.01.25 um 23:13 schrieb Steve Wedge, W1ES/4 via groups.io:

Folks ¡ª

I have someone asking me to get their R7 to work with a TR7. I just want to make sure that the connectors and cables are still obtainable.

Any insights into this?

Steve Wedge, W1ES

Time flies like an arrow. Fruit flies like a banana.

Sent from [Proton Mail]() for iOS



Re: Using an R7A with a TR7A

 

Yes, if you are willing to build you own. An example of the control cable has already been posted to this thread. FWIW I used low capacitance coax for the PTO and 40MHz reference signals but RG-174 or even RG-58 should be OK.

For the RX antenna path you need a pair of cables with RCA connectors on each end. Good quality RG-58A/U is fine. There is a jumper inside the TR7 that needs to be cut to pass the RX antenna path through the R7. The beauty of this system is you can either use the TX antenna for RX on both rigs or switch a separate RX antenna to either rig. This is also a handy place to insert things like an RX preamp or a noise phaser.

Speaker audio can optionally be passed from the TR7 through the R7 via a 1/4 inch to RCA plug cable.

On Sun, 19 Jan 2025 22:13:15 +0000
"Steve Wedge, W1ES/4 via groups.io" <w1es@...> wrote:

Folks ¡ª

I have someone asking me to get their R7 to work with a TR7. I just want to make sure that the connectors and cables are still obtainable.

Any insights into this?

Steve Wedge, W1ES
--

73

-Jim
NU0C


4-Line Crystals for 10M

 

I think someone was having problems with two of the 10M bands with a 4-line rig recently. I happened to see these and thought I'd pass the ad along:



Thanks,
Barry - N4BUQ


Re: PS7 Fault, Troubleshooting & Repair

 

Thank you, Jim. This weekend while using the TR7/PS7 in the NA QSO Party, the PS7 tripped out a couple of times. I went back in this evening and recalibrated the overcurrent setting based on your referenced article. It now trips out right at 30 amps.?


Re: Using an R7A with a TR7A

 

¿ªÔÆÌåÓý

Steve,

?

The attached is the cable that you can build.? It is what I am using for my R7 / TR7 transceive?

?

73

Dale

AF7WH

?

From: [email protected] <[email protected]> On Behalf Of Steve Wedge, W1ES/4 via groups.io
Sent: Sunday, January 19, 2025 2:13 PM
To: [email protected]
Subject: [DRAKE-RADIO] Using an R7A with a TR7A

?

Folks ¡ª

?

I have someone asking me to get their R7 to work with a TR7. I just want to make sure that the connectors and cables are still obtainable.?

?

Any insights into this?

?

Steve Wedge, W1ES

?

Time flies like an arrow. Fruit flies like a banana.

?

?

Sent from for iOS


Using an R7A with a TR7A

 

Folks ¡ª

I have someone asking me to get their R7 to work with a TR7. I just want to make sure that the connectors and cables are still obtainable.?

Any insights into this?

Steve Wedge, W1ES

Time flies like an arrow. Fruit flies like a banana.


Sent from for iOS


Re: Replacement Male connector for 2BQ?

 

I meant replace with DIN connector. That looks pretty old-school with a metal plug.?


Re: The Hum-Less 2B

 

I've got a 2B to recap, and I agree....? with the Qmultiplier? it's a fantastic vintage CW rig.? I pair mine with the flavor of the day CW rig and it's perfect for that.

I found those capacitor boards on ebay from the seller Affinity for Artifacts for about $3 ea, or with caps for 9-10$.? Makes for a nice replacement at a modest price.
There's a variety of shapes and sizes, but here's a sample
?
?
John K5MO
?


TR-4C excess drive on 20m

 

¿ªÔÆÌåÓý

Gentleman;

Recently I acquired a TR-4C / VF-4C in good shape for my needs. Realigned it following the manual and after that I got the following CW power at 115Vac mains:

10m = 135W = 450mA
15m = 150W = 440mA
20m = 175W = 460mA
40m = 205W = 430mA
80m = 210W = 450mA

After tuning I usually set the XMTR GAIN / X-CW up to the point where power / plate current does not rise anymore.

For every band this point falls from 9 to 10 o'clock, except 20m where this point occur around 1 or 2 o'clock.

I always use between every mic / radio a small audio compressor / limiter based on the MAX9814 chip. Two objectives: keep audio level constant of course and avoid mic inputs overload. Good results on different combinations of radio / mics (JBL headset / IC 735, Elecraft K3S or Elecraft MH2 hand mic X TR-4C).

I noticed that on 20m seems that there's excess of drive on TR-4C. I understood that TX AGC is not a "real ALC" but sort of clamper (?), despite of the behavior I measured (e.g. variable negative voltage feed back to TX IF Amp G1, keeping the SSB envelope in a good shape). But looks like it's not behaving as it should on 20m only. I measured the same variable negative voltage at IF Amp G1, basically the same as any other band.

Attached there's a picture of a waveform monitor, long letter "O". I'm aware that 20 and 80m does not use the xtal oscillator so VFO connect direct to TX mixer and may be an higher level of injection can be the responsible.

But 80m behaves equally to any other band up to 10m, the exception is 20m.

The average power is easily detected at any analog wattmeter I have, during normal speech any band ranges from 25-35W but 20m varies from 70 to 80W.

Any clues why 20m "chain" is behaving like this?

73, Marcus PY2PLL.



Drake 5 pin accessory connector

 

I'm talking with a guy that is having samples made of this connector even as we speak/type.

When this comes to pass I'll post the info, but it looks quite promising.
?
John K5MO