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NOS TR-4Cw RIT

 



I've never seen one with the purple tag on the PLATE control before and it does look like an open box/never-used rig.

One thing to be cautious of is that trapped moisture in that factory bag can wreak variable havoc inside.? I bought a B Line station that was almost never used but had been stored in their original packing and the outer cabinets had spots of bubbling in the paint and there was a small amount of mould on the wiring.? The copper chassis were and are still mint on them and the mould was rectified by doing a full wash and dry.? I? swapped cabinets with the equipment I was replacing with these and sold them with photos of the blemishes.

I do see some white spots in places that could be mould.? Still, it's essentially an unused rig that's 45 years old and will need to be brought up slowly to reform the capacitors, but man! what a find!

Steve Wedge, W1ES/4

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

Sent with secure email.


Re: FS-4B (with frequency counter)

 

Very good Bernie.? I had forgotten UNO does have an xtal.? Are you using my "cal" mode to get it exactly on frequency?
Since it is a fudge, how well does it keep it over the PTO range?

The ATMega328 has a clocked counter input so it is limited to 6.4MHz with the 16MHz main clock.? Which is fine since the PTO is 5.5MHz max.
It would be good if the counter could go to 35MHz so we could just read the INJ line...? PICs can do that, an outboard PIC is what I have considered.

I don't see how dividing and then multiplying would help...?

73,
Gary
WB6OGD

?


Re: FS-4B (with frequency counter)

 

?I used ?Arduino UNOs in my two FS-4B systems which gives reasonable stability with a real ?XTAL can on the UNO.

?

The frequency counter code for the FS-4B is a really some software magic that cascades two 16 bit counters in the Arduino.


The upper bound for the counter code is about 6 MHz or so. ?I suspect that hardware ?dividing the Drake PTO frequency by two or three before feeding it to the software counter may result in a better result. The resulting counter frequency can be easily upscaled in software.


The main objective of this project was simplicity and cost effectiveness. ¡­?
--
73, Bernie. VE3FWF
Real?radios glow in the dark


Re: wtb: repairable ac-3 or ac-4

 

Hi Mike!

Very good point!? Words to the wise, for sure.

Jim
KD0WF
=======


Re: A good Day at the Flea Market

 

Congrats on your great finds! DSP noise reduction plays well with the TR7. I have a JPS NIR-12 and a ClearSpeech base. They complement each other nicely. Some tasks are better with one or the other.

These gadgets are designed to work with speaker levels. You may not have enough low level audio to get the best performance out of the DSP. However it is possible to achieve what you want to try without modding the rig. You have an audio out jack on the back that is basically audio at the top of the volume control. Assuming your MFJ has a high impedance audio input plug it in there. The MFJ has its own volume control and audio PA. Connect the output of the MFJ to a decent communications speaker and see how it works.

Something else to think about, that RX antenna loop is a handy place to insert stuff like a preamp or a noise phaser. You will also want that path to be intact if you ever take the plunge and get an R7 receiver.

73

-Jim
NU0C

On Sun, 14 May 2023 14:49:49 -0700
"jerry-KF6VB" <jerry@...> wrote:

Well, that DSP audio filter should play very nicely with my TR-7. Maybe
the noise reduction will help with that endless grinding noise I hear on
40.

The TR-7 has a couple of RCA jacks on the back. They connect the
receiver to the antenna. So you can disconnect them and use a separate
antenna with the receiver. I'm thinking of modifying that - I don't
have the luxury of separate antennas ( HOA ). I could stick those two
BNCs in the audio chain before the speaker amp. That way, the DSP could
work with low-level audio. Of course, I can just plug it into the
speaker output.


A good Day at the Flea Market

 

Here in Silicon Valley, we have been ham-swap-less for a couple of years. First COVID killed it, then the venue ( Fry's Electronics ) went *poof*. Local clubs just managed to restart it last month.

There were some amazing deals. I scored a couple of MFJ items - a RT998 kilowatt remote autotuner for $100, and a 784B tunable DSP filter for a measly $40.
There was a guy with a very cosmetically nice Collins 30L-1 for $180. Yes, not a misprint. It had a cracked glass on the meter, and it needed one tube. But I already have a 30L-1 in the shed, so I passed.

What does that have to do with Drake?

Well, that DSP audio filter should play very nicely with my TR-7. Maybe the noise reduction will help with that endless grinding noise I hear on 40.

The TR-7 has a couple of RCA jacks on the back. They connect the receiver to the antenna. So you can disconnect them and use a separate
antenna with the receiver. I'm thinking of modifying that - I don't have the luxury of separate antennas ( HOA ). I could stick those two
BNCs in the audio chain before the speaker amp. That way, the DSP could work with low-level audio. Of course, I can just plug it into the speaker output.


- Jerry, KF6VB


Re: wtb: repairable ac-3 or ac-4

 

Be sure you ship the speaker cabinet and P/S in separate boxes as stated in the manual. If you ship them as a unit the weight of the P/S will severely damage the speaker cabinet. A seller disregarded my instructions on shipping and my cabinet was destroyed.

Mike/ KE5YTV

On Sunday, May 14, 2023 at 01:40:20 PM CDT, Ronald Beaver <ronaldbeaver1320@...> wrote:


Here's the pictures.? Don't know how much shipping would be but I get an estimate.

Ron WB4OQL?
Clyde, NC

On Sun, May 14, 2023, 8:51 AM Jim Linsenbardt <jim.linsenbardt@...> wrote:
Hi Ron and All,

Ron, I'd be interested in your ac-3 and speaker but, unfortunately,I won't be making the trip to the Hamvention. (My loss, I know!??) Would you be willing to ship? My zip is 65201. Pics would be great,or course!

73's to all who have chimed in!

Jim
KD0WF


Re: FS-4B (with frequency counter)

 

¿ªÔÆÌåÓý

I can send it to you, BUT..
It is totally un-supported. ?I am not sure I understand it at this point.
It is a two part system, one in the rx, one in the tx, talking over a one wire bus.
I posted the basics of the system a while back.
Let me know if you really want the code.
BTW, I really like the way it¡¯s working for me now.
73,
Gary?
WB6OGD?



On May 14, 2023, at 11:50 AM, Gilles Delpech <gilles.f1bfu@...> wrote:

?Hi Gary

Where can I find the source code for the FS-5B version?

T3 Gilles
<73.gif>

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979

??Chacun a raison de son propre point de vue, mais il n¡¯est pas impossible que tout le monde ai tort??
Gandhi

Le 14 mai 2023 ¨¤ 16:53, GARY WINBLAD <garywinblad@...> a ¨¦crit :

You want 16MHz..? Like I said in a previous post, it MAY be possible to change the Arduino
to 20MHz but you don't really want the hassle.
There are a lot of 20MHz TCXOs available but 16MHz is rare.
73,
Gary
WB6OGD
?
On 05/14/2023 7:24 AM PDT F1BFU - Fr - 79 <gilles.f1bfu@...> wrote:
?
?
Gary
?
Yes some have a hole that allows access to fine tuning.
it can be supplied for the frequency of 16 mHz or it is necessary to upgrade the frequency of the Nano from 16 to 20 mHz.
?
<screenshot_9036.png>
?
73
<73.gif>

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979
?
??Chacun a raison de son propre point de vue, mais il n¡¯est pas impossible que tout le monde ai tort??
Gandhi

Le 14 mai 2023 ¨¤ 15:51, wb6ogd <garywinblad@...> a ¨¦crit :

Gilles,
The main reason is because I have a better solution for my project.? See photo, the small silver device in the lower left corner under the 25K trimpot.
There hasn't been much interest in the frequency counter is another reason.

BUT, the one you show might work.? The problem is it might be stable but it is not adjustable to exactly 16.0000000MHz so your count will still not
be correct.? BUT, see that little white dot on the main oscillator??? That MIGHT be a sticker and under it might be a trimmer!?? MIGHT.

There are some chinese vendors on ebay that sell just that part (which may be all that is needed) and one or two indicated they could make them 16MHz.


Re: FS-4B (with frequency counter)

F1BFU - Fr - 79
 

¿ªÔÆÌåÓý

Hi Gary

Where can I find the source code for the FS-5B version?

T3 Gilles

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979

??Chacun a raison de son propre point de vue, mais il n¡¯est pas impossible que tout le monde ai tort??
Gandhi

Le 14 mai 2023 ¨¤ 16:53, GARY WINBLAD <garywinblad@...> a ¨¦crit :

You want 16MHz..? Like I said in a previous post, it MAY be possible to change the Arduino
to 20MHz but you don't really want the hassle.
There are a lot of 20MHz TCXOs available but 16MHz is rare.
73,
Gary
WB6OGD
?
On 05/14/2023 7:24 AM PDT F1BFU - Fr - 79 <gilles.f1bfu@...> wrote:
?
?
Gary
?
Yes some have a hole that allows access to fine tuning.
it can be supplied for the frequency of 16 mHz or it is necessary to upgrade the frequency of the Nano from 16 to 20 mHz.
?
<screenshot_9036.png>
?
73
<73.gif>

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979
?
??Chacun a raison de son propre point de vue, mais il n¡¯est pas impossible que tout le monde ai tort??
Gandhi

Le 14 mai 2023 ¨¤ 15:51, wb6ogd <garywinblad@...> a ¨¦crit :

Gilles,
The main reason is because I have a better solution for my project.? See photo, the small silver device in the lower left corner under the 25K trimpot.
There hasn't been much interest in the frequency counter is another reason.

BUT, the one you show might work.? The problem is it might be stable but it is not adjustable to exactly 16.0000000MHz so your count will still not
be correct.? BUT, see that little white dot on the main oscillator??? That MIGHT be a sticker and under it might be a trimmer!?? MIGHT.

There are some chinese vendors on ebay that sell just that part (which may be all that is needed) and one or two indicated they could make them 16MHz.


Re: wtb: repairable ac-3 or ac-4

 

Here's the pictures.? Don't know how much shipping would be but I get an estimate.

Ron WB4OQL?
Clyde, NC

On Sun, May 14, 2023, 8:51 AM Jim Linsenbardt <jim.linsenbardt@...> wrote:
Hi Ron and All,

Ron, I'd be interested in your ac-3 and speaker but, unfortunately,I won't be making the trip to the Hamvention. (My loss, I know!??) Would you be willing to ship? My zip is 65201. Pics would be great,or course!

73's to all who have chimed in!

Jim
KD0WF


Re: FS-4B (with frequency counter)

 

You want 16MHz..? Like I said in a previous post, it MAY be possible to change the Arduino
to 20MHz but you don't really want the hassle.
There are a lot of 20MHz TCXOs available but 16MHz is rare.
73,
Gary
WB6OGD
?

On 05/14/2023 7:24 AM PDT F1BFU - Fr - 79 <gilles.f1bfu@...> wrote:
?
?
Gary
?
Yes some have a hole that allows access to fine tuning.
it can be supplied for the frequency of 16 mHz or it is necessary to upgrade the frequency of the Nano from 16 to 20 mHz.
?
?
73

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979
?
??Chacun a raison de son propre point de vue, mais il n¡¯est pas impossible que tout le monde ai tort??
Gandhi

Le 14 mai 2023 ¨¤ 15:51, wb6ogd <garywinblad@...> a ¨¦crit :

Gilles,
The main reason is because I have a better solution for my project.? See photo, the small silver device in the lower left corner under the 25K trimpot.
There hasn't been much interest in the frequency counter is another reason.

BUT, the one you show might work.? The problem is it might be stable but it is not adjustable to exactly 16.0000000MHz so your count will still not
be correct.? BUT, see that little white dot on the main oscillator??? That MIGHT be a sticker and under it might be a trimmer!?? MIGHT.

There are some chinese vendors on ebay that sell just that part (which may be all that is needed) and one or two indicated they could make them 16MHz.


Re: FS-4B (with frequency counter)

F1BFU - Fr - 79
 

¿ªÔÆÌåÓý

Gary

Yes some have a hole that allows access to fine tuning.
it can be supplied for the frequency of 16 mHz or it is necessary to upgrade the frequency of the Nano from 16 to 20 mHz.


73

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979

??Chacun a raison de son propre point de vue, mais il n¡¯est pas impossible que tout le monde ai tort??
Gandhi

Le 14 mai 2023 ¨¤ 15:51, wb6ogd <garywinblad@...> a ¨¦crit :

Gilles,
The main reason is because I have a better solution for my project.? See photo, the small silver device in the lower left corner under the 25K trimpot.
There hasn't been much interest in the frequency counter is another reason.

BUT, the one you show might work.? The problem is it might be stable but it is not adjustable to exactly 16.0000000MHz so your count will still not
be correct.? BUT, see that little white dot on the main oscillator??? That MIGHT be a sticker and under it might be a trimmer!?? MIGHT.

There are some chinese vendors on ebay that sell just that part (which may be all that is needed) and one or two indicated they could make them 16MHz.


Re: FS-4B (with frequency counter)

 

Gilles,
The main reason is because I have a better solution for my project.? See photo, the small silver device in the lower left corner under the 25K trimpot.
There hasn't been much interest in the frequency counter is another reason.

BUT, the one you show might work.? The problem is it might be stable but it is not adjustable to exactly 16.0000000MHz so your count will still not
be correct.? BUT, see that little white dot on the main oscillator??? That MIGHT be a sticker and under it might be a trimmer!?? MIGHT.

There are some chinese vendors on ebay that sell just that part (which may be all that is needed) and one or two indicated they could make them 16MHz.
73,
Gary
WB6OGD


Re: wtb: repairable ac-3 or ac-4

 

Hi Ron and All,

Ron, I'd be interested in your ac-3 and speaker but, unfortunately,I won't be making the trip to the Hamvention. (My loss, I know!??) Would you be willing to ship? My zip is 65201. Pics would be great,or course!

73's to all who have chimed in!

Jim
KD0WF


Re: FS-4B (with frequency counter)

F1BFU - Fr - 79
 

¿ªÔÆÌåÓý

Hi Garry

Why doesn't your solution use an external clock oscillator with a 16mHz OCXO like this


features are

Specification:
Operating voltage: + 5V dc / +/- 5%
Operating current: 20mA (MAX)
Output waveform: TTL/CMOS
Duty Cycle: 40/60%
Frequency Stability Vs Temp: +/- 0.2ppm (-10~+60C)
Size: 20.8x13.2x15mm
Aging: +/- 0.1ppm/year.
Input voltage: DC6V-10V

73 Gilles

Gilles F1BFU since 1969
GQRPClub 15889?
QRP ARCI 16979

??Le vieux monde se meurt, le nouveau monde tarde ¨¤ appara?tre et dans ce clair-obscur surgissent les monstres¡­???
Antonio Gramsci (1891-1937)

Le 13 mai 2023 ¨¤ 22:49, wb6ogd <garywinblad@...> a ¨¦crit :

I started a new thread based on a comment by Gilles on Doug's talking FS-4A thread.

YES, the frequency counter in my FS-4B is less than desirable.? This is due to the ceramic resonator that is the time base on the cheap Arduino Nano boards.
The resonator has quite a warm up drift but after its temperature is fully warmed, it is "pretty" stable.? Since a counter needs a stable gate signal, this is a problem.

I found that you can provide an external clock signal to the Nano board rather simply.? See attached photo.
If you lift the two ATMega pins on the corner and solder a fine jumper to the second pin, you can supply an external 16MHz clock without an changes to the fuses
or Arduino code.? 0-3.3V or 0-5V squarewave is what you want to apply.? To get accurate frequency counting, it needs to be exactly 16.0000MHz and stable.

I was able to find a small $3.50USD clock chip at Mouser with temp compensation AND a voltage controlled freq trim pin.? Unfortunately they don't have these anymore
and I haven't been able to find them anywhere else.? You could make your own with a crystal and a trimmer cap... maybe use a logic gate oscillator or a transistor?
Maybe you can bring out two jumpers and get the ATMega into crystal oscillator mode by itself?

My workaround was a "calibrate" mode in the FS-5B code.. not ideal but after warmup it works pretty well.

I have also been looking for? a substitute for the Nano.? I thought I found it in the STM32 boards which have a crystal, are very advanced over the ATMega but?
unfortunately their software includes the FreeRTOS real time operating system with random interrupts to look for task switching.? The frequency counter works
great most of the time until the random interrupt corrupts... bummer.? Nobody seems to know how to shut down the RTOS... especially me.
NOTE: the Nano did have a similar problem with the millisecond counter interrupting but I did figure out how to stop that during freq counts.
If anyone knows a good cheap little computer board like the Nano but with a crystal and available freq counter code, let me know.

My FS-5 in both my R-4B (frankenstein!) and T-4XB have great stable counters using Nanos, so it is possible.
73,


Re: FS-4B (with frequency counter)

 

Peter,
See the Files section for
$14 Homebrew FS-4B

That version has the frequency counter.? I tuses an ATMega internal Timer for the one second gate.
The code came from an Arduino library, I didn't write it.

I believe the 1PPS is not that accurate by itself but it corrects over time.? My GPS based frequency standard corrects over something like a minute and a half.
But, give it a try, maybe that could be a solution.

But too, for a digital dial, you want faster response than 1 second..? I use a 100ms gate for 10Hz resolution, that works well for me.

73,
Gary
WB6OGD

?


Re: RIFA Capacitors

 

If you have a proper size 24V fan then use it, but don't discount 12V models. They draw very little current and a 27-100 ohm 1/2w resistor in series with the positive lead will run it at whatever speed you want/ I often do this with 12V fans where full output is not needed. Just don't go too high or it won't start. I guess a rule of thumb is no less than half voltage. A 12V fan usually does not start running on 5V.
--
Doug, WA3DSP


Re: wtb: repairable ac-3 or ac-4

 

Dave,

Forgot to mention I also have a MS4 for sale..I would be willing to make a package deal if your interested.

Thanks,

Bill N3WM

On Saturday, May 13, 2023 at 09:35:30 PM EDT, N3WM - Bill via groups.io <n3wm@...> wrote:


Hi Dave,

I have a spare AC4 that needs recapping that I will sell¡­.it does not work.

Price is $125 + shipping from 23323 (Chesapeake, Va)

73¡¯²õ

Bill N3WM


On May 13, 2023, at 7:49 PM, Ronald Beaver <Ronaldbeaver1320@...> wrote:

?
Hi Jim,
I have a AC3 with speaker that you could use.? It has not been upgraded .
I will take some pictures of it and send them to you.
Are you planning on being at the Dayton hamvention?

Thanks,
Ron WB4OQL
Clyde, NC

On Thu, May 11, 2023 at 6:52?PM Jim Linsenbardt <jim.linsenbardt@...> wrote:
Hi to all!

I recently got a TR-3 functional and hope to use it on some of the vintage nets. I'm now looking for a repairable power supply to pair with it (with or without speaker.) If you happen to have one, please let me know.

73's and best wishes

Jim
KD0WF


Re: FS-4B (with frequency counter)

 

Hi Gary,

Do you have some Arduino code somewhere showing how to use it as a counter?

I am also wondering if you would be better off connecting an accurate clock (such as the 1pps on a GPS module or from an OXCO) then using interupts to gate the frequency input. I have built an Arduino based WSPR generator designed by W3PM some years ago and it is accurate to less than 1 part in 10Million.

Cheers,
Peter - VK2AN


Re: RV-4C

 

Good news Sean.? Thanks for letting me know.? I'd still open the RV-4C box and check out some of those larger resistors as well, if you have not yet done that.

Enjoy the TR-4Cw/RV-4C combo!

73
Peter
VE7PS

On Sat, May 13, 2023 at 5:51?PM Sean (KK6BEB) <seanlynch@...> wrote:
Peter, not only did the?De-oxit?fix the audio output issue, it brought back the VFO lamp! Thank you ! 73 Sean/KK6BEB

On Sat, May 13, 2023 at 7:02?AM Sean (KK6BEB) via <seanlynch=[email protected]> wrote:
Thanks so much Peter, really appreciate the thoughtful/thorough response here. Will absolutely follow your advice.

Sean
KK6BEB?

On Fri, May 12, 2023 at 10:55 PM VE7PS <ve7ps@...> wrote:
Sean:

Suggest checking two things first....

1) There are some power resistors in the RV-4C that get quite hot and can change value.? Check all of those to make sure they are OK and within spec. I have had to change some of these in the RV-4 and RV-4C's.

2) Be VERY sure the connector in the bottom of the TR-4Cw and the cable end connector of the RV-4C are VERY clean.? Use De-oxit D5 if you have?it.

I have found these connectors to be more troublesome than they should be at times.

While you are at it with the contact cleaner, make sure the VFO selector switch in the RV-4C is clean too.

Nice radios....I have a TR-CW/rit hooked up to an RV-4C here.??

73
Peter
VE7PS

On Fri, May 12, 2023 at 10:12?PM Sean (KK6BEB) <seanlynch@...> wrote:
Hey gang, I recently acquired a TR-4Cw and RV-4C. Both work great however I noticed a big reduction in audio when I switch to using the RV-4C¡¯s VFO. I¡¯m guessing I have a bad/degraded tube in the RV-4C but not sure yet.?

I made a short video. Would appreciate your thoughts on this:


Sean
KK6BEB?



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