[sdiy] 4 channel mixer of signals with frequencies between 2Mhz and lower.. any circuits available.. ??

Roman Sowa modular at go2.pl
Fri Sep 29 12:14:15 CEST 2023


Come on, this is basicaly almost a DC signal, let's not overkill this!
I especially liked as someone joked about doing it digitally in FPGA.

In the old days of analog television, this was called "video bandwidth" 
and what comes wit it - huge variety of video opamps, with enough power, 
bandwidth and low distortion to use in such scenario. My prefered 
all-purpose models were AD818 and AD817, but that was 25 years ago. 
Nowadays there should be hundreds of better and cheaper opamps. Just 
build resistive adder like you would do for CV in modular synth, the 
only difference being resistor values to provide matched load impedance 
for individual transmitters. The opamp will provide enough gain and 
output power to drive antenna directly with those few miliwatts.

Roman


W dniu 2023-09-28 o 23:02, Jean-Pierre Desrochers pisze:
> Here is what I'm trying to do as an experiment.
> 
> I have 4 small AM transmitters transmitting at 600, 900, 1200 and 1600Khz.
> At about 10mW of power each.
> I was thinking about mixing the 4 frequencies as a single unit
> that I could adjust the final output transmitted on a small antenna.
> That's my idea so far..
> 
> 
>> -----Message d'origine-----
>> De : Synth-diy <synth-diy-bounces at synth-diy.org> De la part de Gordonjcp
>> Envoyé : 28 septembre 2023 16:46
>> À : synth-diy at synth-diy.org
>> Objet : Re: [sdiy] 4 channel mixer of signals with frequencies between
> 2Mhz
>> and lower.. any circuits available.. ??
>>
>> On Thu, Sep 28, 2023 at 03:17:56PM -0400, Jean-Pierre Desrochers wrote:
>>> Hi all,
>>>
>>>
>>>
>>> This is an out off topics question but I will ask you anyway..
>>>
>>>
>>>
>>> I want to build a 4 channel mixer that would receive signal
>>> frequencies between 2Mhz and lower one channel..
>>> These 4 frequencies won't change. They will be fixed.
>>>
>>> Google would give me lots of Radio/Ham solutions that imply the use of
>>> tuning coils and such things I don't want to get into.
>>>
>>> The idea would be to use ready available opamps with high bandwidth
>>> with the use of resistors and caps only. Gain would be of one.
>>
>> For the avoidance of the XY Problem, what exactly are you trying to do?
>>
>> --
>> Gordonjcp
>>
>> _______________________________________________
>> Synth-diy mailing list
>> Synth-diy at synth-diy.org
>> http://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
> 
> 
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org


More information about the Synth-diy mailing list