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1/22/2020 12:12:56 PM
Posted: 12/29/2014 5:11:52 PM EST
The UPS man dropped off the new Samlex power supply & VGS-1 (voice guide option) today while we were out.

The Samlex 1235M got set up first. Not much to that job, just set up a couple of 10 AWG THHN wires with straight poles crimped on one end & Anderson PowerPoles on the other. Used some heat shrink to keep things neat and made a few wraps around an iron powder toroid just for grins...

No smoke, no buzzing, no new background noises when the TS-590S was turned on & flipped through the bands. Key down on full power CW showed about 17A getting pulled on the gauge & the voltage stayed put.

I have had a china made SO-3 TCXO ($20 vs $109 for the Kenwood version) lying around for a couple of weeks, so it was time to open the box & get things installed. Both the voice guide & the TCXO install on the face of the bottom board of the TS-590S, These are the only installable options for a TS-590S.

Turn the TS-590S on it's back, unscrew 10 small screws & the bottom cover comes right off.

The VGS-1 (voice guide) adds a number of functions to the TS-590S. It primarily acts as an aid for visually impaired operators, reading out band changes, meter values, etc. It also lets you retroactively capture the preceeding 30 seconds of received audio for replay/review. To install, remove four screws and the module cover to expose the voice guide socket.

The voice guide module came with some foam rubber pads to fix it securely between board & module cover. A larger strip with adhesive on one side is adhered to the back side of the module. A slightly thicker pad with adhesive on both sides gets secured to the plug side of the module. You position the assembly over the socket and press it to click into place.

Replace the module cover & screws and that part is done.

The Kenwood version of the TCXO is just a mounted crystal. The user removes a small board from the radio and has to solder the crystal to the board. The clone I bought came already mounted on an equivilant board. The purpose of the module is to provide improved frequency stability over time and despite temperature changes.

This is how it looks before the TCXO is installed.

The first thing I did was to un-jumper two points, per the install instructions. I placed the jumpers on one pin on each position for storage.

Then it was just a matter of swapping the new board assembly for the old one & plugging the wire header back in.

Buttoned it back up & gave it a smoke test. The magic smoke stayed inside (where it belongs )

The voice guide announced itself on power-up and announced band changes as I traversed them. The box appears to be still on frequency. I checked at 30m (10.000.00) and it sounded like what I expected (did not try alignment testing ). Also hit some known net locations & did not see any anomalous behavior. Made a few QSO's & life seems good...


Link Posted: 12/29/2014 5:15:01 PM EST
[Last Edit: 12/29/2014 6:08:41 PM EST by K9-Bob]
I also bought one of those Chinese TCXO's for my TS-480 and it worked perfectly. It was within 5 hz off WWV, so I left it as is.

The TCXO was well worth the money. I think mine was a bit orver $20.00 shipped from China.

You can use Fldigi to check your TCXO install against WWV using its frequency analysis mode.

Fldigi Link
Link Posted: 12/29/2014 6:17:32 PM EST
[Last Edit: 12/29/2014 6:18:39 PM EST by 444]
Do you have a link for the Chinese TCXO ?

How close to WWV were you before the TCXO ?
Link Posted: 12/29/2014 6:51:54 PM EST
[Last Edit: 12/29/2014 7:05:11 PM EST by nikdfish]
Not sure if I am reading it right w/fldigi. Set freq to 9999 Mhz & cursor offset to 1000. Value on analysis line shows 1000000x.xx where x.xx varies from about -0.28 (i.e. 9999999.78) to about +1.35 at extremes ... generally running +0.30 -> +0.70, so maybe a tad high? (assuming even distribution random +/- variation).

So maybe +/- 0.15 PPM @ 10 Mhz (in terms of short term variability)?

Link Posted: 12/29/2014 6:57:49 PM EST
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By 444:
Do you have a link for the Chinese TCXO ?

How close to WWV were you before the TCXO ?
View Quote

Sorry to admit I didn't test before the swap ... figured it would either work or not work.

Got mine from seller on Amazon.com "Leaning Tech". Currently out of stock there. Should still be a bunch on Ebay & some other locations.

Link Posted: 12/29/2014 7:29:10 PM EST
Great post, Nick, and good job remembering to take the pictures at the various steps. I always forget that part.

I got the VGS-1 too, and the first thing I did was turn off the voice announcements so she'd stop jabbering every time I changed something. I only wanted it to record and playback stuff.

I also got the Kenwood TXCO. I was tempted to get the Chinese one on Ebay but I went for the OEM one. Some of the pads on on the PCB didn't want to stick to solder very well no matter how I cleaned or fluxed them but I got it done.

I followed the Kenwood alignment instructions using my GPSDO referenced Flex 5000 as well as my GPSDO referenced test gear after letting the 590 warm up for a long time. I don't have any exact numbers but it wasn't off by much to start with. The alignment procedure sounds a little hokey but is actually very good and is the same thing done when using much older radios with marker oscillators or WWV.

I think the TXCO is mainly just needed when running JT-65 and similar digi modes, or perhaps with a transverter. It helps keep your frequency from moving around a little bit. The average guy using voice, CW, RTTY, or etc. wouldn't notice much difference with or without it. Easily half of the hams out there aren't exactly on the frequency that they think they are, but most are close enough that it doesn't really matter.
Link Posted: 12/29/2014 8:24:32 PM EST
I found them on eBay.
I might as well get one.

I have no real use for one but think it is cool. I have the GPSDO on my Flex 6700 and had a radidium reference oscillator on my Flex 1500; again, for no good reason.

It was cool on the 1500 to tune in WWV and then throw the switch for the reference oscillator and see the radio snap over a few htz to the exact frequency.
Link Posted: 12/29/2014 9:26:43 PM EST
[Last Edit: 12/29/2014 10:21:28 PM EST by nikdfish]
Looked around & found some descriptions of using the Fldigi freq analysis to check set frequency accuracy. Anyway, went back & followed an instruction list set up for MARS operations. Looks like my set is typically less than 0.5 Hz off the target 10 Mhz. on the low side at this point in time (per Fldigi freq analysis). Second to second variability is in the neighborhood of 0.05 Hz or less

This is after a restart after being off an hour (much less warm-up than first test). I'll check again after an extended on period to see what the offset from ideal is after warm-up.

ETA: after running a bit over an hour in receive mode, the analysis window is showing about a +0.45 Hz over the target 10Mhz. Second to second variability seems to be typically +/- 0.03 Hz with the largest single one second changes seen being ballpark +/- 0.20 Hz.
I'll leave it running overnight & check in the AM.

Link Posted: 12/29/2014 9:47:22 PM EST
[Last Edit: 12/29/2014 9:47:49 PM EST by K9-Bob]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By nikdfish:
Not sure if I am reading it right w/fldigi. Set freq to 9999 Mhz & cursor offset to 1000. Value on analysis line shows 1000000x.xx where x.xx varies from about -0.28 (i.e. 9999999.78) to about +1.35 at extremes ... generally running +0.30 -> +0.70, so maybe a tad high? (assuming even distribution random +/- variation).

So maybe +/- 0.15 PPM @ 10 Mhz (in terms of short term variability)?

View Quote

Fldigi PDF

Here is the link that I used to check my rig.

It may explain it a little better for you.
Link Posted: 12/29/2014 10:39:44 PM EST
[Last Edit: 12/29/2014 10:40:46 PM EST by nikdfish]
I found that same pdf just before you posted. That is the sequence I used this last go-round.

Here is the display after the unit had been running 90 minutes or so...

0.25 Hz off when the snap-shot was taken

Link Posted: 12/30/2014 12:31:50 AM EST
[Last Edit: 12/30/2014 12:41:26 AM EST by K9-Bob]
That's close enough for government work, so I would leave it as is.

I think the TCXO really starts the shine the higher you go in frequency. I especially noticed it on 6m when running JT65 or JT9.
Link Posted: 12/30/2014 8:23:26 AM EST
[Last Edit: 12/30/2014 8:25:05 AM EST by nikdfish]
Did another snapshot after set has been on & receiving for another 8 hours. Looks like it is up about 1 Hz from startup. (was seeing about +1.4 at the peaks) Second to second variation is still about the same...

Link Posted: 12/30/2014 10:42:06 AM EST
[Last Edit: 12/30/2014 10:51:48 AM EST by 444]
I just tried this using my Flex 6700 and the GPSDO and you are about as close as I am.

If I am doing this right, I am around 1 hz. It varies above and below that. I might go as high as 1.4 and down to .8

This is with the radio turned on for about 5 minutes and the GPS is locked on 11 satellites.
Link Posted: 1/19/2015 10:48:25 AM EST
[Last Edit: 1/19/2015 10:51:06 AM EST by 444]
After reading this the first time, I ordered all the stuff and just got done putting the Voice Guide and the TCXO into my TS-590.
Thank you for posting this.
The voice guide works, now I will fire up FLDIGI and see what happens. I did look at it prior to putting in the TCXO and while it was pretty much right on freq. It drifted a lot more than my Flex 6700 with the GPSDO. Will see if things improved with the TCXO.

While I had it apart I turned all the trimmer caps all the way to the right to get more power out.

No, No, I make joke. Me funny guy.
Link Posted: 1/19/2015 10:59:24 AM EST
[Last Edit: 1/19/2015 11:18:12 AM EST by 444]
With no warm up, this thing is now drifting at most .75 hz

As time goes on, I see it drifting maybe 1.3 hz or so. About what my Flex 6700 does with the GPSDO
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