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 1 
 on: Today at 11:35:10 AM 
Started by ki4nr - Last post by VE7RF
Tom

I heard you on the air a while back and your voice sounds just fine for radio, maybe not a big broadcaster voice but better than average. As for me, I have decent voice for radio too, some what like you except I sound young. I turned 60 a month ago and I been told by many people I sound like I'm in my early 40's or younger and are quite surprised at my real age.

Oh yes the Aphex 104 ... Can't stand that thing, nothing like artificial bass to ruin things. It was all the rage around 2000 and many of my friends had them. Drove me nuts with that sound. I use to resort to taking my IF shift or DSP high cut and remove that annoying bass from my receiver. Lucky it seem to be a passing fad and I don't hear much of them anymore.

Yep 4 khz ESSB sounds unreal, the clarity and definition is off the charts. It's really that good when done up right. When I was experimenting with 6 khz  SSB I found that 4 khz was the best overall bandwidth. Just enough for the sound we were looking for  (and wide enough to make the transmitter transparent) and not to much to bother other hams on the band. Also it was easy to listen to on RX with noisy bands.

I'm not sure if you ever listen to 80 hz to 6.1 kHz of flat RX SSB but its very harsh on noisy band like 75 meters. It's really bright and sounds unnatural when listening to band noise with good speakers or headphones. I could only take a little while of it before being fatigued and always grabbing the RF gain control ( wide AM is kind of the same ) But 4 khz on the other hand is perfect. Band noise sounds natural and it's easy to listen to.

I have a Kenwood TS-930 that is moded up with 4 khz Inrad filter in the high IF and 4 khz Collins filter in the 455 IF all audio circuits set up to match the filters and it sounds unreal on receive and transmit at 80 hz to 4.1 khz

Is your 1000D stock ??  have you change the filters out to wider Inrads ??

I have seen pictures of your builds and very very impressive, I wish I had that motivation and enthusiasm. I like to restore the old classic Nipponese boatancher like the Kenwood 940 and 930. I make a few things here and there, but thats about it. I'm really thinking about building a LD Mosfet amp in the future, I want to get totally away from tubes in linears. My big thing is modifying new & old radios and repairing, coming up with all kinds of crazy modifications.

I understand the AM comradery and that's cool. I like AM & SSB and enjoy both. I think the love for AM comes from my CB days. But I have to say there is quite of bit of dislike for ESSB & SSB on this forum ( under the surface ) and on the bands.The term slopbucket and others terms say it all, doesn't bother me ....  but diehard AMers & boatancher enthusiasts seem to be polarized on one mind set of thinking.

J


Nothing wrong with the  Aphex 104.  I currently use an Aphex 204.  I also use a Behringer  EX-3200.  BUT they have to be tweaked very very carefully.  I use a behringer MIC-2200 mic pre-amp with my  RE-27....and it has one parametric EQ  built into each channel. I use the eq to do a cut at aprx  160 hz..and  1.7 octaves wide.  Then it all sounds good.  I also tried doing the same cut at  160 hz in my main EQ..and can't get the same effect...and I still don't know why.

Both my FT-1000-MP-MK-V's are modified with 6 khz filters..and that combo is good up to aprx 5.7 khz wide.  (ESSB mode).  Even on a noisy 75m band,  I don't find the 5.7 khz fatiguing on  RX.   I also use aprx  4 or  4.5 khz  BW.  That too works good.

Since I have 2  x channels on all the rack gear, I typ use the left channels on  TX..and have experimented with some of the right channels on RX.   By adding artificial harmonics on RX, and also eq'ing the 'new harmonics', I found that  super weak  KH6's, just above the noise on the upper bands  improved a bunch for intelligibility.  A  real eye opener.  No luck with the ..'all mode squelch' on  ESSB, so tried  several
experiments using the  downward expander on  RX.  That was used in conjunction with backing the RF gain way down, pre-amp off, and 6db attenuation dialed in.    Everybody stops talking..and the band noise just fades away.  Again, it took many tries to get this right.

I could never get the RF compressor in the MK-V to ever work right, until I shifted the Cxr  osc over by  40 hz, then bingo,  I managed to nail it. With most of the essb  folks on the west coast being loud to begin with, those that are a bit bass heavy is no big deal.  Under marginal conditions, you have to switch to plan B.

The amount of hrs I have spent tweaking  stuff is unreal.   After all is said and done..it works for me only.  I used to heat this all the time, whereby another ham would drop by..and get on the   mic..and it's good, but overly  brilliant.  Plan C  was  stored eq pre-sets for when other folks came over to operate.

What would be a big help on  RX, is..'hang agc'... like  80-90 msecs.  I have not figured out how to implement it... yet.   I'm still  bumbling about on how to get the audio to sound right on AM.   I also have 2 x  FT-1000D's...and only one is modified..for  essb.   I also tried some very brief tests with FM on 10m, but did  not pursue it further.

Right now, I'm modifying the cooling in all  4 x of my  drake L4B amplifiers, adding Eimac style tapered chimneys..and also  EBM-papst blowers, and power supply mods.    The best I can come up with is aprx  300w  CXR /1200 pep  for AM mode..on  75m.

I'm also in the middle of  building another  B+  supply for my HB  3CX-3000A7 amp.  We  are allowed a full  750 watts of AM cxr..here in Canada  ( measured at the feedpoint of the ant, after feedline loss)   so to do  AM right, factoring in  feedline losses,  I need a  tube that does  800+  cxr..and 3.2 kw +  pep...and more pep, if positive modulation is more the typ  125+  %.

Too many projects these days, not enough time.

Jim   VE7RF

 2 
 on: Today at 09:47:28 AM 
Started by KD2AZI - Last post by W2PFY
Quote
VL is Variable Link (you can bend the inside coil back and forth)

A better way to adjust the link rather than bending them, would be to put a 100-250 variable cap in series with one end of the link to ground. You could use combinations of switched fixed caps along with the variable. I did that with my other BC-610 on the output links where you are quite often trimming up the final plate current. By just setting the link to max coupling and using the variable cap in the link, it felt like I was tuning a pi net circuit. I should do that on my newer BC-610D but I got lazy!

 3 
 on: Today at 02:56:38 AM 
Started by W2PFY - Last post by DMOD
Quote
What transformer are you referring to, the interstage driver transformer for driving the grids of an 810 or the modulation transformer?

Well in this case I am looking to drive a couple 100TH tubes in my BC-610. I am already doing that but I wanted to get more exact on my approach in driving the tubes.
I haven't sat down and done any of the figuring out of the turns ratio etc with the information everyone has sent me on the board as yet.

I already have at least by the people who have heard my transmitter a very descent sounding 610 but I wanted to tailor it a bit more, with a transformer that that meets the specs rather than a transformer that I just happened to have, on hand that I think is not quite what I need to meet the voltages and current for the tubes. Its just an experiment to see if I can get more positive peaks than what I get now with the same settings on my PA amp. Just playing around here to see what's what Tongue Tongue

Here ya go!

BTW, the OX and OY resistors are the Ohmite non-inductive ceramic resistors:

https://www.ohmite.com/catalog/ox-oy-series?filter=category%3A2%3AOX%2FOY%20Series#cds-attribute-category

and highly recommended.

Phil

 4 
 on: Today at 12:51:06 AM 
Started by Knightt150 - Last post by K6JEK
Maybe whatever this guy is using

https://www.youtube.com/watch?v=xLKq0hgKn9o

 5 
 on: Today at 12:40:48 AM 
Started by ki4nr - Last post by WB4AIO
[...]
I wanted to post an ESSB recording I heard a few years back but can't find it in my docs.  I think it was by a VE7 or W9 or maybe another ESSB enthusiast.  The audio was magnificent for a 4KHz bandwidth. Except for a few artifacts, it sounded just like AM.  Do you remember seeing it or maybe have a copy? I posted it in one of the threads on this BB too.

Right now I'm busy mounting parts on my new single 3-500Z amplifier. Baby Blue panel with viewing window. Once the metalwork is done, it's like building a Heathkit. Watch for some pics soon.

T



Good luck with the new rig!

My favorite eSSB group is the 3630 gang. 7.5+ kHz audio all the way, baby.

Here's a sample:

http://liberty.3950.net/N9VR%20NU9N%20et%20al%20on%20influence%20of%20eSSB%203630%20kHz%202019-1202_081912_B1.mp3

73,

Kevin, WB4AIO.

 6 
 on: Today at 12:25:02 AM 
Started by W2PFY - Last post by W2PFY
Quote
What transformer are you referring to, the interstage driver transformer for driving the grids of an 810 or the modulation transformer?

Well in this case I am looking to drive a couple 100TH tubes in my BC-610. I am already doing that but I wanted to get more exact on my approach in driving the tubes.
I haven't sat down and done any of the figuring out of the turns ratio etc with the information everyone has sent me on the board as yet.

I already have at least by the people who have heard my transmitter a very descent sounding 610 but I wanted to tailor it a bit more, with a transformer that that meets the specs rather than a transformer that I just happened to have, on hand that I think is not quite what I need to meet the voltages and current for the tubes. Its just an experiment to see if I can get more positive peaks than what I get now with the same settings on my PA amp. Just playing around here to see what's what Tongue Tongue

 7 
 on: Yesterday at 11:33:09 PM 
Started by ki4nr - Last post by DMOD
KI4NR,

I use a Hallicrafters S-108, a Mohawk RX-1, and an Icom-7200 and I have never heard excessive bass from any AM operator. Can you identify the call letters of these supposed "high bass" operators.

My speakers are various speakers with most of them being 8" to 12" wide range GP speakers with no crossovers. No, no bass problems.

The AM operators with which I have had QSO's all have  a natural sound with no excessive highs or lows and full modulation (high modulation percentages) resulting in good audio levels.

KI4NR
Quote
...They do sound pretty good I have to admit, but still with lots of unnecessary bass. But that's the operator choice and his audio signature sound, Ok up close with strong signals, but not in the distance. Now this is with the good stations and operators that know what's going on. The average AM stations either boatancher or rice box sounds crummy, strong or weak for what I have been hearing. The average SSB station running the newer DSP rigs sound much better overall....

I still do not know where you're coming up with the phrase, "unnecessary bass." Have you had your hearing checked by a degreed Audiologist? I had my hearing checked two weeks ago with the resulting curve plotted and I hear no emphasized or "unnecessary bass" from AM operators.

KI4NR:
Quote
The average SSB station running the newer DSP rigs sound much better overall....

No they don't. I have heard rare exceptions, but 99.5% of the SSB operators use questionable mikes, they use equalizers which they know nothing about as to how to set them up properly (splattering up and down the band), and they incessantly talk over each other.

When attempting to cram extended audio into a DSP that is programmed for a bandwidth of ~ 3kHz with sharp rolloff filter programming, the result is restricted audio that sounds like it's coming from a Disney studio.

I do hope you find the problem in your equipment that is causing this alleged emphasized bass because it appears none of us are having this problem.


Phil - AC0OB




 8 
 on: Yesterday at 11:23:03 PM 
Started by W2PFY - Last post by DMOD
How do I figure out what voltages I can expect to receive from an audio transformer when all I have is the value in ohms of the transformer?

For example I'm told on a Johnson Desk KW to drive the 810 modulator tubes to use a transformer that has a 1500 ohm secondary. ( this is an example only, the book may may call for something different) The primary could be anything up to 600 ohms.

So the object is to know how many volts I can get out of a transformer to drive the class B grids. I know that if I have the transformer all I would have to do is run 10 volts AC into it to get the turns ratio, but what if I don't have the transformer in my shop?

Inquiring dummies like me need to know:)

Thanks Terry AKA Captain Marvelous in another life..........

What transformer are you referring to, the interstage driver transformer for driving the grids of an 810 or the modulation transformer?

If you are referring to a driver transformer for driving the grids of an 810 you need about 175 Volts peak audio voltage X 65 mA peak audio current from the center Tap to each outside winding.

Phil

 9 
 on: Yesterday at 10:19:51 PM 
Started by Knightt150 - Last post by Knightt150
 Hello: I have a ON and OFF buzzing noise on my receiver ON 5 seconds OFF 5 seconds almost all day. It seems to be mainly on the 40 meter band and up higher. I think it is local but don't know. What is a good portable receiver that is made to hunt down interference like this.

John W9BFO

 10 
 on: Yesterday at 10:03:12 PM 
Started by Opcom - Last post by Opcom

This Sadelco 7600 signal level meter was given to me from an estate, and was labeled as working as of 7-20-2000. I know who did this and that they had also replaced the NiCd cells at the time.

The AC adapter is missing, I can't find any data on it, and the cells are of course dead now, or most likely ruined from storage.

It looks like it covers 54MHz to 800MHz? continuously in 4 bands. from TV CH 2-86 according to the dial.  (86?? -thought 83 was the top.)

I'm looking for the details on the AC adapter or even the manual so I can get it working, power it up,  and check my antenna signal strength on a couple of antennas I use to monitor interesting signals.

I know it's an AM board but I have no where else to ask about test equipment where people might have experience with this kind of thing.

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