HQ Oscilloscope & Spectrum is an app by Yury Grebenkin in the Tools category, listed since at least April 2019. It has no native code, so it runs on any Android processor.
It asks for 1 permission, 1 of them sensitive: record audio.
What's new in v1.4
Real-time statistics.
Spectrum track.
Hold all.
Description
From the listing uploaded by “catappult”.
High quality digital storage oscilloscope with spectrum view.
Sample rate: 48 kHz
Buffer size: 1 second
Signal source: microphone
-- touch screen navigation
-- high precision playback
-- real-time statistics
-- trigger
-- spectrum track
-- 4096 frequencies spectrum resolution
MANUAL
All controls are visible on the screen.
Oscilloscope and spectrum views are independent of each other.
OSCILLOSCOPE
Turn on the view.
Scale division values are displayed in the bottom-left corner as second x discrete.
Signal level scale is on the right side.
Touch and drag with one finger to navigate a waveform, touch with two fingers to zoom.
Press HOLD to freeze the buffer.
While in HOLD mode it is possible to navigate to the past up to one second.
Time shift in microseconds, if present, appears in the top-left corner.
Press TRIG to bring the ruler on if you need to measure exact values of individual discretes.
Move the ruler with one finger.
An exact signal level value corresponding to the ruler position is displayed in the top-left corner.
Press PLAY to enable repeated playback of the buffer cut by time window bounds.
Press STAT to enable real-time statistics:
max -- highest sample value
min -- lowest sample value
avg -- average sample value
mdz -- mean deviation around zero
sd -- standard deviation
sum -- sum of sample values
int -- area between sound wave and zero
Triggering with holdoff:
Zoom in and adjust scale division values as needed.
Press TRIG and position the ruler according to a signal level and a time distance to trigger on a correct part of a signal.
When triggered press HOLD and then release TRIG to study an interesting part of a waveform with navigation, zoom and playback.
Holdoff period is defined by a time distance between the ruler and the right edge of the view.
One shot triggering:
Make initial adjustments, press TRIG and position the ruler as when triggering with holdoff.
Release TRIG and press TRIG again to flush the buffer.
Make sure that there is no signal captured in the view.
Press HOLD.
After this point the oscilloscope is waiting for just one first trigger event.
Release HOLD and press HOLD again to reload for another single shot.
Release TRIG to study a waveform.
The trigger point is on the rising edge of a signal above or equal to zero and on the falling edge of a signal below zero.
SPECTRUM
Turn on the view.
Move the vertical ruler to display frequency with maximum precision at any position along the spectrum view.
Press HOLD to freeze.
Press AUTO to make the ruler follow dominant frequency.
Note that it is possible to move the ruler while in HOLD mode and to temporarily move the ruler while in AUTO mode.
Press HLDA to freeze both spectrum and oscilloscope.
Pressed HLDA button manifests that views have been set on hold together and display mutually relative data.
Press TRAC to switch to spectrum track mode.
While in spectrum track mode the vertical ruler turns into scale with marks for seconds and tens of seconds.
Security & authenticity
Security rating: Trusted
Signing certificate
Certificate issued to “Yury Grebenkin”The developer's name — though anyone can put any name in a certificate.
Uploaded by “catappult”Platinum tier · 1,377 followers · uploading since 2018
Scans and ratings come from the source store; the certificate comparisons are AAPKs's own, made from the files' published signatures. AAPKs doesn't scan files itself — compare the MD5 and signer after downloading.
Permissions (1)
HQ Oscilloscope & Spectrum requests 1 permission, 1 of them sensitive.
Record audio (microphone)Sensitiveandroid.permission.RECORD_AUDIO
Required hardware & features
Microphoneandroid.hardware.microphone
HQ Oscilloscope & Spectrum APK: questions and answers
Can I install this APK over the version I already have?
Only if it is signed with the same certificate as the copy on your phone and isn't an older version. If Android says “App not installed”, the certificates differ; uninstalling your copy first works but deletes its data unless it is backed up.
Is the HQ Oscilloscope & Spectrum APK safe?
No one can promise that a file is safe, but some things can be checked. The source store rates this file Trusted. After downloading, check that the file's MD5 is 0a587ab7d9a48329f9007adc9386dc55.