Search found 16 matches

by crin
Thu Jan 28, 2021 5:36 am
Forum: Test, Measurement and Repair
Topic: how to test relays for phono signals
Replies: 15
Views: 3532

Re: how to test relays for phono signals

crin wrote: ↑ is there a particular reason why you suggest the 1510 instead of the 1512? The datasheet is clear. Here high gain is needed. that's what puzzles me. according to the data sheets, both chips provide up to 60 dB of gain. the only difference i can see WRT gain is that the 1510 is specifi...
by crin
Wed Jan 27, 2021 9:46 pm
Forum: Test, Measurement and Repair
Topic: how to test relays for phono signals
Replies: 15
Views: 3532

Re: how to test relays for phono signals

The 1 K Rbias might not be enough. With the concern being the low levels of MC switching pick 10-100Ω. If the relay load resistor is 100Ω then you only need 2 mV of common mode voltage at the input to the diff amp to produce a contact current of 20 µA. not sure i understand you – are you suggesting...
by crin
Tue Jan 26, 2021 10:30 am
Forum: Test, Measurement and Repair
Topic: how to test relays for phono signals
Replies: 15
Views: 3532

Re: how to test relays for phono signals

i'm trying to figure your proposed null test with gain – would you place the inputs of the 1512 at C and NC and measure what comes out after 60 dB of amplification? but if there's no signal, how can it be distorted? but the idea of a null test has a lot of appeal. i'm still trying to figure out if t...
by crin
Mon Jan 25, 2021 10:53 am
Forum: Test, Measurement and Repair
Topic: how to test relays for phono signals
Replies: 15
Views: 3532

Re: how to test relays for phono signals?

i have the boost stages (waynes flat MM preamps), and i could also use the inverse RIAA filter to create a RIAA emphasized signal. but what kind of signals do i use, what kind of "error" could a relay possibly cause? one thing is the outgassing of plastic and environmental pollution seeping in throu...
by crin
Fri Jan 22, 2021 7:48 pm
Forum: Build
Topic: Phono Transfer System Construction Information
Replies: 172
Views: 170778

Re: Phono Transfer System Construction Information

somehow, this board looks familiar… :lol: reminds me of east texas: sparsely populated :mrgreen:
by crin
Fri Jan 22, 2021 7:34 pm
Forum: Test, Measurement and Repair
Topic: how to test relays for phono signals
Replies: 15
Views: 3532

how to test relays for phono signals

i'm looking for suggestions on how to test relays for use at phono (MM) levels: how to set up the test for repeatable results, what signals to use to detect measurable differences, what to look for etc. background: i'm building a flat phono preamp with several of wayne's MM and MC boards, various in...
by crin
Mon Sep 07, 2020 11:36 am
Forum: The Peabody Lounge
Topic: US Postal Service Air/Sea Shipment Diversion
Replies: 12
Views: 12254

Re: US Postal Service Air/Sea Shipment Diversion

a feast for dumpster divers… :D do they still put cheques in the mail in the US?

(good observation re the time of the crime. the shadows look more like 7-/8-ish. i think they made pre-dawn illegal a long time ago.)
by crin
Wed Aug 26, 2020 8:28 am
Forum: Pro Audio Design
Topic: Cheap Surround sound buffer/level shifter
Replies: 51
Views: 26347

Re: Cheap Surround sound buffer/level shifter

sorry to chime in so late… but which Hypex modules are you using? they vary quite a bit in terms of RMS input for full power output… i assembled a pair of NC400 monobloc amp kits last year. the DIY kits contain everything neccessary to build a complete amp, including a SMPS for each amp module. the ...
by crin
Wed Jul 29, 2020 9:58 am
Forum: The Peabody Lounge
Topic: US Postal Service Air/Sea Shipment Diversion
Replies: 12
Views: 12254

Re: US Postal Service Air/Sea Shipment Diversion

i think the corona-pile-up mostly affected parcels shipped in late march, all of april and the first half of may. by now, things are slower than usually but stuff from the US arrives in europe within 10…14 days – shipped with USPS.
by crin
Sun Jul 12, 2020 8:22 pm
Forum: The Peabody Lounge
Topic: US Postal Service Air/Sea Shipment Diversion
Replies: 12
Views: 12254

Re: US Postal Service Air/Sea Shipment Diversion

things have cooled down considerably. i ordered a ton of inner and outer sleeves for LPs from sleevecity. they shipped in late may and the package arrived 10 days later. postage for packages from the US to europe has literally exploded in the last couple of years. shipping one LP used to be around $...