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Casio FX-602P - Printable Version

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RE: Casio FX-602P - Jlouis - 10-11-2019 07:43 PM

(10-11-2019 04:22 PM)Csaba Tizedes Wrote:  Is there any experience about which voice recorder applicable to FA-1 and FA-2? Any advice helps.

Thanks,
Csaba

Do you mean a modern digital voice recorder?

Thats a good question , that I'd like to know too.

Cheers


RE: Casio FX-602P - Csaba Tizedes - 10-12-2019 08:31 AM

Yes, I mean casette recorder, but I want to use a digital audio recorder instead of casette recorder.

On page 2 in the manual there are technical requirements listed, you can find here: http://casio.ledudu.com/images/pockets/casio/periphs/manuelFa1.pdf#page=2, is it a special ones or this is common for all recorders available on the market?

My other idea is to use my phone (Android) with a special cable to connect to the headset connector (if this kind cable is available - edit: maybe this one: https://www.amazon.com/Kingtop-Adapter-Tablet-Headsets-Version/dp/B01I3A47I4?ref_=fsclp_pl_dp_2).

And yes, the fx-50x models works without REMOTE connector.


Csaba


RE: Casio FX-602P - ijabbott - 10-12-2019 11:39 AM

(10-11-2019 05:03 PM)Dave Britten Wrote:  
(10-11-2019 04:22 PM)Csaba Tizedes Wrote:  Is there any experience about which voice recorder applicable to FA-1 and FA-2? Any advice helps.

Thanks,
Csaba

I use a Tandy Computer Cassette Recorder with my FA-3. It works quite well, and is in fact the only recorder I've been able to make work with it, out of a handful of cassette and digital recorders. I suspect it's got something to do with either the strong line-level output of this recorder, or mono vs. stereo jacks.

I used a similar recorder in the UK, the WH Smith CCR800 Computer Compatible Cassette Recorder. It had a switch for "normal" and "compute mode", which fiddled with the levels. However, I didn't get that until 1982 when bought a ZX Spectrum, so I must have been using the family's regular old cassette recorder before then. (It must have been around 1980 when I bought the FX-502P and FA-1.)


RE: Casio FX-602P - BobVA - 10-14-2019 02:51 AM

On one of the retro computer mailing lists (Tandy M100) I haunt they've had mixed success with digital recorders instead of a cassette machine, apparently due to the voice/music/human hearing optimized compression schemes they typically use (e.g. MP3) not working so well with the data tones.

Best practice seems to be to use an uncompressed format (e.g. WAV), but YMMV depending on the recorder / computer in question.


RE: Casio FX-602P - robve - 12-24-2023 03:13 PM

(10-11-2019 04:22 PM)Csaba Tizedes Wrote:  Is there any experience about which voice recorder applicable to FA-1 and FA-2? Any advice helps.

I recently found an FA-2 on an auction site and was looking forward to use it with my fx-602. But it didn't work when saving and loading to a voice memo recorder, which saves the recordings in wav format. Fresh AAs with the FA-2 didn't help. I use this wav file recording setup with Sharp pocket computers, which worked for me (although I prefer to use PocketTools to transfer files).

After reading this thread (thanks to all for posting, this forum is an invaluable resource!) and with a bit of experimentation I got my casio fx-602 and my "new" FA-2 working to save and load fx-602 programs and data Smile

Experimenting a bit with Audacity shows that the recorded wav file amplitude is too low. Converting the wav file with +20dB and playing it at max volume worked. I don't know if this is a peculiar thing of my FA-2, so perhaps others don't need as much as +20dB amp up.

My setup:
  • record wav files (PCM) at 1024kbps with a digital voice memo recorder (FA-2 white jack to mic input)
  • transfer wav file(s) to a PC over USB, I'm using a Mac
  • play the wav file at +20dB, for example using the built-in MacOS terminal afplay command with option -v 20 and max headset output volume (headset port to FA-2 black jack)

I'm using an inexpensive small digital voice memo recorder for this, nothing fancy. It can save wav files at different bit rates. 1024kbps works for me.

Again, I don't know if this low amp output issue is a problem with my FA-2. But I'm happy it works now.

- Rob


RE: Casio FX-602P - BobVA - 12-26-2023 02:43 AM

Great you got that working - nice hack with Audacity /afplay!

Interesting that the recording is coming out so low. Just to be clear, when you play it back it in Audacity, it's showing that it's about 20dB below peaking out (0 dB) on the level meter?

I couldn't find an English FA-2 manual, only German, but I was able to glean that the FA-2 output is at a very low, microphone level (3mV). Is is possible that the input on your recorder is expecting a line level (around 1000 mV)? The manual should tell you. If it's a microphone input is there's some way to adjust the input level / sensitivity? Sometimes there's a switch or software setting for the input gain.


RE: Casio FX-602P - ijabbott - 12-26-2023 05:20 PM

(12-24-2023 03:13 PM)robve Wrote:  Experimenting a bit with Audacity shows that the recorded wav file amplitude is too low. Converting the wav file with +20dB and playing it at max volume worked. I don't know if this is a peculiar thing of my FA-2, so perhaps others don't need as much as +20dB amp up.

I think the recording level is a bit low compared to line level (but it is intended to drive the microphone input of a cassette recorder). I did mono recordings from two different FA-2 interfaces and an FA-1 interface in Audacity via a cheap, USB audio interface. I couldn't get a signal when connecting the FA's microphone (white) jack directly into the pink, stereo 3.5mm microphone socket, so I connected the FA's microphone jack to a mono 3.5mm to RCA adapter, which was connected to the left input of a dual RCA to stereo 3.5mm jack, which was connected to the pink microphone input of the USB audio interface. Audacity was set up to record a mono track from the left channel.

After recording from each FA interface in Audacity, I selected some of the main part of the recording (after the end of the lead-in tone) and used the Analyze -> Measure RMS option. I got the following results:

FA-1: −28.6 dB
First FA-2: −32.4 dB
Second FA-2: −29.9 dB

I used the same, fresh batteries in both FA-2s. The FA-1 does not use batteries.