Just kidding... That's actually a mic from an old Heathkit Benton Harbor Lunchbox.
I continue to get good advice from listeners on the mic issue. I hope to put this to rest soon -- then we'll shift away from AF back to RF. Several listeners advised me to stick to SolderSmoke's "homebrew or roadkill" ethos, and to avoid the temptation to solve problems with credit cards. Good advice! People REALLY like the audio with the old decrepit computer mic and the Linux Ubuntu Laptop. So here is what I'm going to do: I'll go back to that combo, but I will attempt to fix up some of the mechanical problems (the old mic is falling apart and it has all kinds of weird things taped on to it) and the electrical problems (it seems to pick up more AC hum than then D-104). It won't be pretty, but it will be a nice homebrew/roadkill device.
A question for those who expressed support for this mic and for the audio in #129: Didn't you hear the AC hum?
Finding Your Best Crystal Radio 'DX Diode' (Part 2)
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Readers may recall my summertime blog, "*Finding Your Best Crystal Radio
‘DX Diode'*". It described a theoretical method I tried in order to see
which o...
2 hours ago
Bill,
ReplyDeleteI confess I too preferred the af fron the roadkill mic - it's more broadband than the D104 which is clearly designed as a comms mic (ie, no bottom end - it's not needed for inteligable speach, so would give you a wide ssb signal and waste bandspace).
I listen to the podcast downloaded onto my smartphone, which is plugged into the car stereo. I have it cranked fairly high to get over the road noise at 70mph. So as well as a lack of bass, i also heard another radio station down n the noise which started around 25 min 45 sec in.
You really do need some eq on the (roadkill) mic signal. From previous experience, there is great temptation to turn the treble up too far to make it sound "bright". it might be worth listenng to a few decent broadcast stations - just to "get your ear in" so you know what you are trying to achieve. They WILL have eq on the mic, and most probably some compression too. If i get a chance, i'll play with audacity and a few back issues and email some suggestions to you. 73's
Bill,
ReplyDeleteI'm all for roadkill/homebrew, as you know (although, I have no ideas on how to advise you on it, lol!).
Along with the chorus, I too felt that the D104 was WAY too harsh sounding, sort of like those dudes in the pileup with the 1.5kW and over-processed voices shouting "ECHO-BRAVO!" or whatever. Not good. :(
The roadkill mike was far better. More well-rounded audio and more pleasant. No "SSSsss" problems either (those came back with a vengeance on the D104, as noted). And, as stated before, the duct-tape/roadkill nature just works, on a spiritual level. So, roll out some fresh tape and get that baby back on the air, my friend!
73's and thanks for your podcasts, as usual.
I was at XHUDG the other day, the University station. They have Sennheiser (condenser) microphones. ¿Cuánto costaron? How much they cost? A lot. Too much. How about a microphone from say, an old Uher recorder or other high-quality tape recorder? You might have to make impedance match network. BTW, at the radio-t.v. station: no duct tape in site.
ReplyDeleteBill,
ReplyDeleteI guess I just don't have that critical of an ear. I'm more concerned with the content verses the"sss". I thought the D104 was fine except for the broadcast noise, but then my daughter-in-law the audiologist says my ears are messed up anyway. Yes, keep with the homebrew / roadkill path - good for the karma.
Bill,
ReplyDeleteThe Telrad zero power finder would make an excellent finder for your scope. I first used one on my 8 inch Dob. I went from having to sweep back and forth to find a full moon to easily finding galaxies. The Telrad or one similar plus a star map from Sky and Tel is all you need.