The BOM has been checked manually to the layout and to the circuit and you can now get a copy in the link below
X-Altra RIAA Phono EQ Preamp
It seems when I did the original, that the part references on the BOM came out of sync with those on the schematic.
X-Altra RIAA Phono EQ Preamp
It seems when I did the original, that the part references on the BOM came out of sync with those on the schematic.
Hi Bonsai, finally got around to placing orders for components. thanks for your help with the FETs They came promptly as it happened. A have just a few findings & questions...
The Talema Transformer you specified. RS also sell what appears to physically the same beast under the RS pro brand 124-3843. Its half the price, wondered if you considered this? The Talema brand may well meet more standards.. Could be the same part, but then it may have different internal construction, and may generate a stronger field. Anyway I'm going with the Talema as I do not like to change to many things...
I have a problem getting the 2.2uf film cap. Digikey suggest a TDK replacement 495-1127-ND. So I will go with that. Bit concerned though as its a coupling cap, what's your opinion? I do have a couple of the 100V variant, sods law , too big!
Also have issue sourcing the 2 x 2200uf so went with UPM1V222MHD1AA. I prefer using the higher temp 105c caps as I see that translating into longer life.
Anyway I found by splitting between Mouser and Digikey you can avoid carriage charges - just
The Talema Transformer you specified. RS also sell what appears to physically the same beast under the RS pro brand 124-3843. Its half the price, wondered if you considered this? The Talema brand may well meet more standards.. Could be the same part, but then it may have different internal construction, and may generate a stronger field. Anyway I'm going with the Talema as I do not like to change to many things...
I have a problem getting the 2.2uf film cap. Digikey suggest a TDK replacement 495-1127-ND. So I will go with that. Bit concerned though as its a coupling cap, what's your opinion? I do have a couple of the 100V variant, sods law , too big!
Also have issue sourcing the 2 x 2200uf so went with UPM1V222MHD1AA. I prefer using the higher temp 105c caps as I see that translating into longer life.
Anyway I found by splitting between Mouser and Digikey you can avoid carriage charges - just
I just ordered a board. I just completed an Octal Aikido based line stage, but really think a tube phono preamp is probably a bad idea. Bonsai, you said in an earlier post the metal can LSK389s could be used? I have a number from a previous Diyaudio GB, B grade and would love to use them. Are there holes on the board, or is it kind of a hack to use them? I don't mind spending the $ for the right solution... Buying the AudioXpress downloads now, or a subscription if back issues are included. I had a print subscription for years, but they deviated from what I wanted to see around 2010-ish.
Ashley,
C9 and C25 MUST BE REVERSED on the PCB. The schematic is wrong.
Feel free to post questions up here - no problem from my side and other builders to comment and lend a hand.
Please note the BOM and all supplementary information (specs, build doc, user manual, measurement methodology) have been moved onto the audioXpress site and a link to the data pack provided on the hifisonix website.
Here is the link for your convenience: https://audioxpress.com/files/attachment/2734
The zip file is called Russell-X-Altra-AX-Feb2021Updated.zip
Here is the link for your convenience: https://audioxpress.com/files/attachment/2734
The zip file is called Russell-X-Altra-AX-Feb2021Updated.zip
Hi Bonsai, apologies! I got the RS pro transformer part number wrong, its part 124-3847.
Its also the same weight at 110 grams. I bought the Talema variant you specified from RS. I also bought an RS Pro 'clone' - different voltage / rating for a different project. Looks like the same moulded plastic design and labelled much alike...
Its also the same weight at 110 grams. I bought the Talema variant you specified from RS. I also bought an RS Pro 'clone' - different voltage / rating for a different project. Looks like the same moulded plastic design and labelled much alike...
For those that are interested, you can now download Part 1 and Part 2 of the X-Altra MC/MM articles from audioXPress here
Items about: Project Articles | audioXpress
Any questions, I’ll be happy to answer.
Here is a link to the page with the supplemental material detailing how the noise performance was measured, BOM, user manual etc
audioXpress Supplementary Material | audioXpress
Items about: Project Articles | audioXpress
Any questions, I’ll be happy to answer.
Here is a link to the page with the supplemental material detailing how the noise performance was measured, BOM, user manual etc
audioXpress Supplementary Material | audioXpress
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I have all of my passives mounted and have just done my first power up test. Luckily I’m getting about -15.007v and +15.052v at the test points. Huzza! Thanks for the help getting this far. My raw voltages are a bit high at 16v and 31v rather than the suggested 10 and 25v +/- 3vdc. I’m wondering if I should be worried about these input voltages being a bit high or if the regulators will be able to handle the difference.
I’m thinking that this must just be my local voltage and possibly the transformer that I’m using. I’m in Canada where line voltage is 120VAC and I wasn’t able to get RS to ship here so for a transformer I have a YHDC PTC3.2 which is rated at 2x 115v in 15v out.
I also noticed that C55, which is mounted on the bottom of the board, has a +symbol printed beside one mounting hole on the top side of the board and there is also a + symbol printed beside the other lead on the bottom of the board. Which is the proper orientation for this electrolytic cap?
I’m thinking that this must just be my local voltage and possibly the transformer that I’m using. I’m in Canada where line voltage is 120VAC and I wasn’t able to get RS to ship here so for a transformer I have a YHDC PTC3.2 which is rated at 2x 115v in 15v out.
I also noticed that C55, which is mounted on the bottom of the board, has a +symbol printed beside one mounting hole on the top side of the board and there is also a + symbol printed beside the other lead on the bottom of the board. Which is the proper orientation for this electrolytic cap?
I assume you mean this one:
Galaxy 2U w/Steel Covers – diyAudio Store
Yes, I too would lprefer to order from the diyaudio shop..
Galaxy 2U w/Steel Covers – diyAudio Store
Yes, I too would lprefer to order from the diyaudio shop..