Top right widow has information with total calculated voltage over all bins. If there was no 1 kHz signal present, value would represent correct total noise in the fixed 22 Hz – 22 kHz bandwidth. Noise (signal) density over frequency is a correct averaged value for any given frequency axis point. As you pointed out, window skirts or signal phase noise obscure result close to signal frequency. At such low levels I can't tell which is more responsible.
REW is a free software, but documentation is still very good. If you haven't found this already, here is explanation of Real Time Analyzer options:
https://www.roomeqwizard.com/help/help_en-GB/html/spectrum.html
Probably, even professionals like you could find some use for it.
I’m grateful to John Mulcahy (REW author) for making REW available for free.
REW is a free software, but documentation is still very good. If you haven't found this already, here is explanation of Real Time Analyzer options:
https://www.roomeqwizard.com/help/help_en-GB/html/spectrum.html
Probably, even professionals like you could find some use for it.
I’m grateful to John Mulcahy (REW author) for making REW available for free.
I’ve upgraded my measurement equipment with Cosmos APU + Cosmos ADC. New measurement confirms that this signal generator has at 2 Vrms output, distortion at -145 dBc. Measured distortion is actually in the range of residual distortion from measurement equipment, as can be seen at this link:
https://www.diyaudio.com/community/...na-70-to-outperform-apx555b-for-30000.386001/
So, actual distortion could be even lower.
Measurement was taken at 2Vrms for comparison with Victor’s signal generator. At ASR forum and some bloggers (Archimago), measured for Victor’s signal generator -142 to -145 dBc distortion. My measurement of Victor’s generator, using same output level and equipment resulted with 6 dB worse result for Victor’s generator. Seems that all samples are not the same.
I’m waiting for ADC thermostat board add-on, which should improve further lowest measurable distortion levels, so we’ll see.
Another advantage of EOSC is perfectly stable frequency. Cold start is with 996.45 Hz. After hours of operation, frequency is 996.44 Hz. Victor’ generator from start to stable condition changes frequency some 2 Hz. It’s significant issue only with use of precise notch filter (Cosmos APU).
I have one signal generator to many. You can easily guess which one. 🙂
https://www.diyaudio.com/community/...na-70-to-outperform-apx555b-for-30000.386001/
So, actual distortion could be even lower.
Measurement was taken at 2Vrms for comparison with Victor’s signal generator. At ASR forum and some bloggers (Archimago), measured for Victor’s signal generator -142 to -145 dBc distortion. My measurement of Victor’s generator, using same output level and equipment resulted with 6 dB worse result for Victor’s generator. Seems that all samples are not the same.
I’m waiting for ADC thermostat board add-on, which should improve further lowest measurable distortion levels, so we’ll see.
Another advantage of EOSC is perfectly stable frequency. Cold start is with 996.45 Hz. After hours of operation, frequency is 996.44 Hz. Victor’ generator from start to stable condition changes frequency some 2 Hz. It’s significant issue only with use of precise notch filter (Cosmos APU).
I have one signal generator to many. You can easily guess which one. 🙂
Attachments
A slight shift in frequency doesn't matter as long as the fundamental frequency is sufficiently suppressed by the notch and doesn't hit 0dB.
Hello Gari,
Yes, PCB are available.
I've answered you by PM.
Regards.
Frex
Yes, PCB are available.
I've answered you by PM.
Regards.
Frex
Hello Frex.
Thank you for the quick reply.
I can't send you a PM, even though I've joined here since 2009, because I've posted so rarely that the moderator thinks I'm a new member. That's why I'm under moderation. You can send me a PM, but I can't send you. I would like to order this oscillator circuit board from you, but I can't because I can't send you a PM.
Therefore, I ask that if you could send me a PM with your email address so that we can agree on the details of the order.
Is this going to get too complicated...but thanks anyway.
gari
Thank you for the quick reply.
I can't send you a PM, even though I've joined here since 2009, because I've posted so rarely that the moderator thinks I'm a new member. That's why I'm under moderation. You can send me a PM, but I can't send you. I would like to order this oscillator circuit board from you, but I can't because I can't send you a PM.
Therefore, I ask that if you could send me a PM with your email address so that we can agree on the details of the order.
Is this going to get too complicated...but thanks anyway.
gari
Hello,
I received fine your PM gari, and I answered your PM with another PM.
There is my personal email inside it.
If you don't have it, you can then contact me using this email :
contact "at" onaudio.net
Regards
Frex
I received fine your PM gari, and I answered your PM with another PM.
There is my personal email inside it.
If you don't have it, you can then contact me using this email :
contact "at" onaudio.net
Regards
Frex
Hi Frex, thank you for the great work on AN67. I am interested in purchasing 1 PCB of EOSC10KV4.02. I want to send you a private message, please contact me via PM or "huangshangjie@hq-mart.com", the new V4 schematic (pdf): EOSC10KV4.01_sch cannot be downloaded. Thanks! Huang Sheng
Hello Stephanoo,
Yes, I have some bare PCB available.
The price is unchanged, 18€ for each bare PCB including shipping in simple priority letter outside EU (no tracking)
For registered (tracked) letter, add +5€.
(For several PCB ordered, I make a discount).
I provide as usual a full design folder with many documents as soon payment done.
If you are interested, please send me PM.
Best regards.
Frex
Yes, I have some bare PCB available.
The price is unchanged, 18€ for each bare PCB including shipping in simple priority letter outside EU (no tracking)
For registered (tracked) letter, add +5€.
(For several PCB ordered, I make a discount).
I provide as usual a full design folder with many documents as soon payment done.
If you are interested, please send me PM.
Best regards.
Frex