Basically, not all 9203 units are equals.
The Advanced Photonix PDV-P9203 from Digikey is actually closer to the 9200 spec from SBE and Jameco:
The reason the true 9203 is considered a gold standard for non-custom, DIY photocells is that it has a lower range of light resistance and a higher range of dark resistance.
Like I said in my other thread, I'm not an expert on Univibes but if we were to think of this practically, the following occurs and make the 9203 ideal.:
1.) Think about what it means to have a lower light resistance, i.e. when you feed the LDR a "signal" in the source of a glowing bulb, LED, etc. it resists pulses of light less. So when the bulb is pulsing fast, that translates to rapid changes in the resistance of the LDR, i.e. good fast speed performance.
2.) Think about what it means to have a higher dark resistance, i.e. when you increase the duration of darkness, make the bulb pulses longer, i.e. more darkness, it resists that change. So when the bulb is flashing slower, with longer pulses or durations from light to dark, that translates to slower changes in resistance of the LDR, i.e. good slow speed performance.
To answer your question about the actual device YOU have, let's look at the sheet:
I'm assuming you made a typo and actually have the 5537-1.
That's a fairly good sub for the 9200/AP 9203. The dark resistance is lower and the range of light resistance is higher, so you'll get different perfomance. You'll never get the same super slow, undulating speed performance like if you used a true 9203, but fast speed performance should be good and you can enhance the slow speed by changing the tantalum caps feeding the LFO.
