Hi
I could not download the Discrete line amp BOM on the site. Is the link working? What Solder Tip you used to solder these SMD' components mostly the resistors?
I could not download the Discrete line amp BOM on the site. Is the link working? What Solder Tip you used to solder these SMD' components mostly the resistors?
The soldering iron tip is called a ‘needle point’ tip. Same for the tweezers.
See here https://hifisonix.com/how-to-solder-smd-components/
See here https://hifisonix.com/how-to-solder-smd-components/
Hi Bonsai
thanks for the video link very useful. I could download the BOM But did not understand the description prefix like MSR? which I could identify Resistors to be SMD and LSK 389 but not able to identify other items. Is there a Mouser Part number available for SMD components. No SMD could be easily checked or do you have specific manufacturer for Resistors. I thought of ordering this PCB after checking the list.
Thanks for the support. This discrete preamp has ideal PCB size to fit in to older Audio devices or building simple line level preamp
Kannan
thanks for the video link very useful. I could download the BOM But did not understand the description prefix like MSR? which I could identify Resistors to be SMD and LSK 389 but not able to identify other items. Is there a Mouser Part number available for SMD components. No SMD could be easily checked or do you have specific manufacturer for Resistors. I thought of ordering this PCB after checking the list.
Thanks for the support. This discrete preamp has ideal PCB size to fit in to older Audio devices or building simple line level preamp
Kannan
MSR means Mouser and RS means RS.
When you search for the part on either website, don’t put in the MSR or RS prefix. The part numbers will get you the correct values and manufacturer.
For the LSK 389, you can use a TI JFE2140 (in the SOIC package). Mouser has them in stock.
When you search for the part on either website, don’t put in the MSR or RS prefix. The part numbers will get you the correct values and manufacturer.
For the LSK 389, you can use a TI JFE2140 (in the SOIC package). Mouser has them in stock.
It is just an observation. Hopefully I am wrong. The diodes and caps on low noise 4.9V supply on phono boards seems to be connected reversed. Board may also to be rechecked to confirm.
Thanks
Thanks
The supply is reversed - neg is at the top and pos at the bottom - it looks confusing but its correct
🙂
Yes my aging eyes missed that...should have looked more closely...
A separate document covering the Mini phono stage, like done for HP & Discrete amp. will be very helpful.
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Hi Andrew,
Small question. If one were to use an ALPS 10k/5k log pot for volume, how is it wired to LL or dicrete LL amp inputs? Another thing I noticed that on LL amp there are three outputs with one being aux out (J8) with 100 ohm in series. Should those be used and one marked J3 be left out?
Best Regards
Farooq
Small question. If one were to use an ALPS 10k/5k log pot for volume, how is it wired to LL or dicrete LL amp inputs? Another thing I noticed that on LL amp there are three outputs with one being aux out (J8) with 100 ohm in series. Should those be used and one marked J3 be left out?
Best Regards
Farooq
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The input capacitor for the line amplifier (Kemet R82CC4220Z370K) shown in the BOM is sourced from RS in the UK. I believe an acceptable alternative is available from Mouser (Kemet R82CC4220AA70J), for those in the US.
Another question with respect to the BOM: It appears C14,C15 and C25,C26 are all the same part (2.2uF, polyester film), but have different vendors called out. Were these locations different values at one time during developement? Can they be combined to one BOM entry now?
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They were all the same valud and same spec from Mouser. I’ll amend the BOM to reflect that. Thanks
Hi Andrews,
I was wondering is the Low noise PS 12V output is ok to drive a volume controller motor?
I was wondering is the Low noise PS 12V output is ok to drive a volume controller motor?
I ordered a power supply., but do you have the balanced output board for sale yet? The modular concept is nice but if you had a one-piece board with everything integrated, I might consider building a complete preamp.
Bill
Bill
Bill, the balanced board is available. That will give you left and right balanced outputs plus 2 off left and right unbalanced outputs (the 2 off unbalanced outputs are wired in parallel).
(Your PSU board will leave on Tuesday)
😊
(Your PSU board will leave on Tuesday)
😊
Most motorised pots run off 5V. The remote controller board for the X-Altra Mini II which is coming in a few days uses a bridge driver across a regulated 5 V. The typical current draw is about 100mA (Alps RK27 for example) and the stall current is 2-3x this figure.
I would like to add the balanced board to the psu board order. If you let me know the amount I will PayPal you funds.
Bill
Bill