[hpsdr] PennyWhistle MOSFET's

[Riho B., ES7AAZ]

Helmut, it was a good idea to trace the DAC output. Thanks! I'm much
clearer now. BTW, I'm using a Mercury for that which is actually a very
good spectrum analyzer.

--
*73,*
*Riho ES7AAZ*


Kontakt Riho B., ES7AAZ (<es7aaz at gmail.com>) kirjutas kuupäeval K, 10.
november 2021 kell 19:28:

> Helmut, I don't have much lab instruments currently here. But I have a
> small 50Ω sma dummy load soldered to the piece of coax. If Penelope sees
> 50Ω dummy load the TX carrier signal looks damn clean. So, there is nothing
> wrong with Penelope here. If I connecting the Penelope to the PennyWhistle
> and sending singal out into the 20m delta loop and using small indoor
> antenna for RX the TX carrier looks terrible.
>
> Kontakt Riho B., ES7AAZ (<es7aaz at gmail.com>) kirjutas kuupäeval K, 10.
> november 2021 kell 18:33:
>
>> In Duplex there is only 15cm coax and opened T/R relay here  So, no
>> Mercury overdrive, more likely underload.
>>
>> --
>> *73,*
>> *Riho ES7AAZ*
>>
>> Kontakt Helmut Oeller (<dc6ny at gmx.de>) kirjutas kuupäeval K, 10.
>> november 2021 kell 18:20:
>>
>>> Not sure that you interpret TX display in Duplex mode correctly !?
>>>
>>> 73, Helmut
>>> Am 10.11.2021 um 17:08 schrieb Riho B., ES7AAZ:
>>>
>>> Helmut, thanks for all tips and suggestions. Sure, I will take a look
>>> into it what's going on here. Fortunately I have a Pinocchio as well for
>>>  measurements and troubleshooting. Yes, the PowerSDR shows the signal how
>>> it's going out from DSP.  In Duplex mode it shows how the signal going out
>>> from the radio.
>>>
>>> --
>>> *73,*
>>> *Riho ES7AAZ*
>>>
>>>
>>> Kontakt Helmut Oeller (<dc6ny at gmx.de>) kirjutas kuupäeval K, 10.
>>> november 2021 kell 17:07:
>>>
>>>> Riho, don't give up! Penelope and Pennylane were (are) fine boards.
>>>> Search for the reason. Check as already suggested signal quality at the
>>>> input of amp U6 (OPA2674), check 12V supply voltage for ripple etc. and
>>>> output match (T2). When I recall correctly PowerSDR shows the base-band
>>>> signal in TX mode and not the real output signal. Hence I would
>>>> recommend to use an external analyzer to evaluate the RF signal.
>>>>
>>>> 73, DC6NY
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>
>>
>>
>
> --
> *73,*
> *Riho ES7AAZ*
> *www.qrz.com/ES7AAZ <https://www.qrz.com/db/ES7AAZ>*
>
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