NI PXIe-8370, PCIe-8371, PXI-GPIB upgrade

November 26th, 2016

I was using NI PXIe-8105 embedded controller in my NI PXIe-1062Q chassis but the speed is too slow.  Recently I have acquired the controller card PXIe-8370 (about 800MB/s; pcie x 4).  The PCIe-8371 card can be put  in my computer PCIe x 16 slot (for VGA card) and function perfectly. Mother Board is Gigabyte H77N ITX version. OS is WIN7 64bit version and both the NI and audio precision system two cascade is working fine with an I5-3570K CPU.  The fan noise of the NI chassis is even lower then before and the power loading is lesser without the embedded controller!

.

Without the embedded controller, I lost some I/O like parallel port, GPIB etc… and thus I have to get one more PXI-GPIB card.  Later I find out my Agilent 82357B USB – GPIB controller is also working fine in with NI system.  In the past, I plug the USB into PXIe-8105 but cannot make it work properly!  Thus the PXI-GPIB card become excess!

Key sight DSO-X 3024T firmware update

November 25th, 2016

Keysight has released new firmware 04.08 for DSO-X 3024T and here are the photos of upgrade process.  The whole process take about 5-6 mins.

It has made lots of changes in this version and details refer to website link:

http://www.keysight.com/main/software.jspx?ckey=2573488&lc=eng&cc=SG&nid=-32541.1150350&id=2573488

Audio Precision USB APIB Adapter (inside photos)

November 19th, 2016

I am using PCMCIA to APIB to control my AP system two cascade under winxp.  The PC is celeron with PCMCIA slot and thus is running very slow.  One way is to use a PCI to PCMCIA adapter if PC is to be upgraded.  I just have one i5  – 3570K with 8GB ram and ITX Mother Board and thus no PCI slot!

Recently I saw a old AP USB to APIB adapter on ebay for about US$350 and thus I think it is time to upgrade the speed of the AP system. 

Here is some photos inside the adapter.

USB interface – Cypress CY7C68014A-128AXC

74ATC240 / 74ACT245

4420P-G01 / 4816P 

See photos for details.

Ekras distribution amplifier inside photo

November 6th, 2016

This is Korean distribution power amp and record some photos before throw away.

Crown DSi 4000 repair

October 16th, 2016

The symptom is can power on, display show LOW RAIL but no sound.  LED on main board not flash.  +rail at heat sink at 89V (normal at +30V with no signal) and -rail at heatsink -30V (normal).  The cause of defect is due to probe around fan control circuit and suddenly power off and then show defect symptom above.  The fan noise is really too loud for home use and but if not set the fan on, the drop down resistors are too hot and also the +/- 15 regulator is also hot and cause the pcb to be brownish color.

The failure is due to U17 LM358 defective (body very hot) and thus replace a similar op-amp M5238.  Reboot the set and it is working again.  The +rail voltage will only drop to +30V after the set is fully boot up.  Tested for 2 hrs output and confirm the set is fully functional again.  See some AP measurement.

Note that with no input, the output is quite noisy, may be due to the switch mode supply.  Also at 1kHz, the harmonics distortion is quite a lot.  S/N is about 95dB, while the spec quoted for 100dB.  Thus this amp does not sound very quiet at background but good for high power drive for PA and Cinema use.