[JaMo]

There is something cryptic mentioned "DC13-15Venter". Is that 13-15V center positive?

If You look at the circuit board in one of the pictures, You can read (mirrored) +12 to +15 V. I haven't got mine yet but I expect center positive. Will ask the seller if not obvious when having it at hand.
/Jan

 

[roni44]

Nice! How long did it take to "discipline" the clock (10.000000 MHz) after locking to the satellite? Just curious as how long the OCXO takes to stabilize compared to the satellite.

Mine took less than a min before it reach 10.0000000mhz, and it will bounce between 9.99999999 to 10.0000000 constantly.

 

[motberg]

Nice! How long did it take to "discipline" the clock (10.000000 MHz) after locking to the satellite? Just curious as how long the OCXO takes to stabilize compared to the satellite.

I did not time it - but seemed about 10 - 15 minutes to fully lock into the GPS system (pretty cool watching that on the display actually.. what times we are living in!). The manual seems to suggest a minimum 30 minutes warm up, then another plateau at around 5 hours and then even further accuracy possible with extended time. I just leave it on 24/7 so far.. Besides the front display there are rear LED indicators to show lock and OCXO temp status.

I just took delivery of a Lightspeed Attenuator and waiting on some DC cables and an interconnect that should arrive this week. So I will soon have a LT3045 LPS powered Lightspeed vol. control between my NOS7 DAC and Master 3 amp with all silver litz interconnects. After I get that broken in a little and familiar with the sound, I will revisit the 10M clock contribution.

(I am now using a generic passive pre and tube buffer, which sounds great but I assume is colored by the RCA NOS 12AU7 clear-top in the path, so for proper clock evaluation I will take the buffer out of the chain.. but my guess is the tube will return the minute I revert to 70's prog-rock )

 

[DACLadder]

@motberg @roni44. That’s quick. I was thinking it would take hours to get the last few decimal places. Thanks!

I had to deep dive my mothballed audio equipment for a S/PDIF cable today and found my old Off Ramp 5 DDC +12V power supply - “Dynamo”. It’s beefy (3A) and low noise. Also found some 50 ohm coax cables. Hopefully, nothing else to buy for 10MHz clock testing!

 

[roni44]

@motberg @roni44. That’s quick. I was thinking it would take hours to get the last few decimal places. Thanks!

I had to deep dive my mothballed audio equipment for a S/PDIF cable today and found my old Off Ramp 5 DDC +12V power supply - “Dynamo”. It’s beefy (3A) and low noise. Also found some 50 ohm coax cables. Hopefully, nothing else to buy for 10MHz clock testing!

I should've mention this, initial boot took less than 10 min to reach 10mhz (I think it was just a bit over 5min), I do turn off clock from time to time and each cycle after initial boot reaches to 10mhz less than a min for me. I am looking into LPS for the clock or ifi ipower, any suggestion will be highly appreciated.

 

[JaMo]

Hi,
A bit OT but anyway related..

One thing I have learned about these OCXO's is that they are very sensitive to the voltage level when feeding them power. A dip or a rise in the power feed is instantly impacting the oven (heating) and secundary the frequency. So for a non-GPS disciplined OCXO a very stable, adjustable LPS is key to get it to work with stability. For the GPS Disciplined this is less important as the discipline algorithms compensates. But a good and precise LPS should be what we all use with our OCXO's. As many of You surely has noticed many of the OCXO's has "DC11.7-12.9V Max 15W" printed. This is mainly because, inside this span a very precise 10.000 000,000(0) Hz will more or less be fixed based on the voltage level. A Youtube clip showed a +12.2V to get the precise target and 12.0V gave a very clear drop in frequency. Start at 12 volts, let heat for a few hours, hook up a scope and fine adjust for a precise 10MHz signal should be the procedure for us/the people without the LCD displays.

By the way...These ovens consumes about 8 watts when heating up and about 2,5 watts running at normal working condition. Good to know I think.


My 2 cents...
/Jan

 

[motberg]

Hi,
A bit OT but anyway related..

One thing I have learned about these OCXO's is that they are very sensitive to the voltage level when feeding them power. A dip or a rise in the power feed is instantly impacting the oven (heating) and secundary the frequency. So for a non-GPS disciplined OCXO a very stable, adjustable LPS is key to get it to work with stability. For the GPS Disciplined this is less important as the discipline algorithms compensates. But a good and precise LPS should be what we all use with our OCXO's. As many of You surely has noticed many of the OCXO's has "DC11.7-12.9V Max 15W" printed. This is mainly because, inside this span a very precise 10.000 000,000(0) Hz will more or less be fixed based on the voltage level. A Youtube clip showed a +12.2V to get the precise target and 12.0V gave a very clear drop in frequency. Start at 12 volts, let heat for a few hours, hook up a scope and fine adjust for a precise 10MHz signal should be the procedure for us/the people without the LCD displays.

By the way...These ovens consumes about 8 watts when heating up and about 2,5 watts running at normal working condition. Good to know I think.


My 2 cents...
/Jan

Wow - interesting info there... this morning I just ordered a DR LT3045 box at 12v, currently using a pretty nice Teradak set at 12.05v iirc... but I have the GPS clock box..
(I noticed that the input voltage range was strangely specific and toleranced out to xx.x V, but did not know why)

I will give the regulator box it a try when it arrives and advise if any problems..
https://www.ldovr.com/product-p/dxp-1a5dsc.htm

Many thanks for the heads-up... great info

 

[DACLadder]

Hi,
A bit OT but anyway related..

One thing I have learned about these OCXO's is that they are very sensitive to the voltage level when feeding them power. A dip or a rise in the power feed is instantly impacting the oven (heating) and secundary the frequency. So for a non-GPS disciplined OCXO a very stable, adjustable LPS is key to get it to work with stability. For the GPS Disciplined this is less important as the discipline algorithms compensates. But a good and precise LPS should be what we all use with our OCXO's. As many of You surely has noticed many of the OCXO's has "DC11.7-12.9V Max 15W" printed. This is mainly because, inside this span a very precise 10.000 000,000(0) Hz will more or less be fixed based on the voltage level. A Youtube clip showed a +12.2V to get the precise target and 12.0V gave a very clear drop in frequency. Start at 12 volts, let heat for a few hours, hook up a scope and fine adjust for a precise 10MHz signal should be the procedure for us/the people without the LCD displays.

By the way...These ovens consumes about 8 watts when heating up and about 2,5 watts running at normal working condition. Good to know I think.
/Jan

Thanks Jan. @FredA mentioned his +12V oscillator would not work with the supplied 1A power supply at startup when the oven was pulling maximum power. The power supply would shut down. I looked at specs for the oscillator on our board and the datasheet states +12V +/- 5%. But the Ebay sale suggests 13 - 15V. We shall see....

 

[DACLadder]

@JaMo I was able to adjust the old Off Ramp 5 power supply output to +12.12V so will give that a try first. I have an oscilloscope and will take a look at the output before connecting to the U16 Thanks!

 

[JaMo]

...the datasheet states +12V +/- 5%. But the Ebay sale suggests 13 - 15V. We shall see

I don't know how efficient the circuit is but I trust the print on the circuit board (+12-+15V) more than the seller. But some circuits uses bleeding resistors in some cases to discharge the circuits fast. Rare but existing and it demands a bit higher voltage. But I still think a powerful enough LPS 12V ~2A will do the job just fine.

I was able to adjust the old Off Ramp 5 power supply output to +12.12V so will give that a try first. I have an oscilloscope and will take a look at the output before connecting to the U16 Thanks!

That sounds good. But wasn't that power supply a 12V 1A..? If so It can be a little weak but it should do the job but take longer before heated up the ovens to working temperature. The inrush current could be a problem though... I intend to use a 12V 2A LPS for this job (@FredA suggestion)

/Jan

 

[DACLadder]

@JaMo The Empirical Audio Dynamo power supply is rated 3 amps by indication on the output plug. It sells for $799 now. There is not $800 worth of parts inside that box!

I think Fred had a weak 1A power supply and the circuit probably draws close to that warming up. 2A should be fine.

 

[JaMo]

@DACLadder :

I haven't got mine yet but I expect center positive. Will ask the seller if not obvious when having it at hand.

Seller has confirmed "center positive"
/Jan

 

[FredA]

Hi guys.

I finally tried the sine output on my ocxo. It sounds better then the square out. A sine output is less demanding to the cable would be my theory. Also the square out is derived from the sine so maybe timing error or noise are introduced.

Compared to the square out, the highs are smoother, the bass seems tighter and resolution is better. Just my very first impressions, not sure of anything but the the highs really seem better. I ordered a second 50ohm cable which hopefully will come in before the first one does.

I should have tried this way sooner!

 

[JaMo]

Hi Fred!
Good to hear about Your progresses in Your setup. Near endgame it seems.. (But I don't believe that for a minute..Ha ha) You are a searcher and discoverer by nature so You will never get full peace... for long at least. Nothing wrong with that. I agree about the square wave and demands of quality on cables.
Question: Do You have any idea of what OCXO You have inside the box? Just curious. But the fact is that a bunch of OCXO's (Double oven clones of the Oscilloquatz 8663 XS) branded UCT-108663 are sold on ebay for USD28+postage from a seller i California. These are NOS and are said to be excellent.
By the way.. My U16's are working fine with v1.4PSA and the 1.61NFB fw's. No flaws, just beuautiful music. Today I have two weeks with power on the GPSDO and with a small reluctance, I have to admit it has already passed the inside Accusilicons in performance. But the "baking" is ongoing and changes still comes and goes.. I expect two more weeks to really know.

/Jan

 

[FredA]

Hi Fred!
Good to hear about Your progresses in Your setup. Near endgame it seems.. (But I don't believe that for a minute..Ha ha) You are a searcher and discoverer by nature so You will never get full peace... for long at least. Nothing wrong with that. I agree about the square wave and demands of quality on cables.
Question: Do You have any idea of what OCXO You have inside the box? Just curious. But the fact is that a bunch of OCXO's (Double oven clones of the Oscilloquatz 8663 XS) branded UCT-108663 are sold on ebay for USD28+postage from a seller i California. These are NOS and are said to be excellent.
By the way.. My U16's are working fine with v1.4PSA and the 1.61NFB fw's. No flaws, just beuautiful music. Today I have two weeks with power on the GPSDO and with a small reluctance, I have admit it has already passed the inside Accusilicons in performance. But the "baking" is ongoing and changes still comes and goes.. I expect two more weeks to really know.

/Jan

You are right. Peace is not for me. Always looking for an upgrade. I am getting the he9 today, or tomorrow.

From all i can tell, i haven't opened the unit, i have a Dapu 055f-ASDD. See this link:

https://www.aliexpress.com/item/329...hweb0_0,searchweb201602_10,searchweb201603_53

With a pi, i have no issue with the u16. With the usbridge, that's another story.