edwards.aus
New Member
Hi all,
I want to build a voice record/play circuit using HK-828. I have attached the datasheet for convinience. I want to use Random Access Type (with 4 message recordings - (Pg 9 of HK-828 datasheet).
I was having some issues with choosing the right speaker. I have an 8Ω 0.25W rated speaker.
According to the datasheet (Pg 11), the speaker pins output a power of 1W to a 16Ω load.
Now, I want to use my 8Ω speaker for this circuit, but I cannot directly put it across the SP+ and SP- pins due to power mismatch.
To overcome this, I thought I might use a seperate audio amplifier. I thought I might work with LM386-N-1 (again datasheet attached for convinience). it is pretty cheap.
Basically I was looking at utilising Application circuit, Amplifier with Gain = 20 Minimum parts (Page 5 of LM386 datasheet). According to the HK datasheet, the Voltage output from the speaker pins is 1.4Vpp. So i might voltage divide with a pot as in the appln. circuit to get 1/10th voltage input and then amplifier gives 20 gain (prolly enough for me).
I have not yet built the circuit although I have bought the components. I am new to electronics and thought I might discuss this approach whether it will work or not.
Await reply in earnest.
Thanks,
Edwards
I want to build a voice record/play circuit using HK-828. I have attached the datasheet for convinience. I want to use Random Access Type (with 4 message recordings - (Pg 9 of HK-828 datasheet).
I was having some issues with choosing the right speaker. I have an 8Ω 0.25W rated speaker.
According to the datasheet (Pg 11), the speaker pins output a power of 1W to a 16Ω load.
Now, I want to use my 8Ω speaker for this circuit, but I cannot directly put it across the SP+ and SP- pins due to power mismatch.
To overcome this, I thought I might use a seperate audio amplifier. I thought I might work with LM386-N-1 (again datasheet attached for convinience). it is pretty cheap.
Basically I was looking at utilising Application circuit, Amplifier with Gain = 20 Minimum parts (Page 5 of LM386 datasheet). According to the HK datasheet, the Voltage output from the speaker pins is 1.4Vpp. So i might voltage divide with a pot as in the appln. circuit to get 1/10th voltage input and then amplifier gives 20 gain (prolly enough for me).
I have not yet built the circuit although I have bought the components. I am new to electronics and thought I might discuss this approach whether it will work or not.
Await reply in earnest.
Thanks,
Edwards