Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1] 2 Next   Go Down
  Print  
Author Topic: TS-830S Mic Gain  (Read 29472 times)
GM8UPI
Member

Posts: 84




Ignore
« on: September 06, 2013, 10:55:25 AM »

Hi folks. My newly acquired TS-830S seems in v good condition. RX works great on all bands. TX also seems good giving 100w+ on all bands, key down, but I note that on max carrier drive, the ALC only reaches 50% of meter scale on 10mtrs. (Goes over full ALC scale on all other bands.) Note key down for a couple of secs only!
No real problem then? Perhaps need to change driver tube in near future.
However my main concern/problem is that when using SSB with MC-50 desk mike, I require to speak-up the mike closer than I would really like (2inches as opposed to around 6-8inches) with mic gain at max. Doing this does give me a good 100w pep.
Will changing to a "good/new" driver tube improve this situation?
Apart from this I am getting excellent audio quality reports.
Any advice on this would be appreciated.
Love this old rig!!!
73
Dave
Logged
KD2DYY
Member

Posts: 45




Ignore
« Reply #1 on: September 06, 2013, 12:01:01 PM »

Dave................... Don't you just love that 830s?Huh? If I could eat a radio it would be that one..... Wonderful!
Look at Ken's web site.......K4EAA.com..... Pay particular attention to the tune up procedure that he details.....Heck , look at his whole site.... He has most ,if not all the answers for these fine radios....
I do agree with you that the driver seems to be getting a little " soft"but let Ken be the educated source of knowledge on your issue..... he is ,truly, the expert.....
There is a Yahoo, "Kenwood" user group that is very knowledgeable as well. I am a member of that group but I warn you that they are VERY technical in thier diagnose and repair procedures......Hold your breath when you post a question and be prepared for shoot back for more info.... They do NOT mess around.... That is a good thing. you want answers, not blase' opinions.
Good luck on finding the answer Dave.... Feel comfortable that thier is a lot of help to any repair/operational issues with these fine old Kenwoods. I'm a believer..... You are ,well, on your way to be one as well.
Get back to me for the particulars on the Yahoo user group if you are interested..... Our Eham.net is great as well.

                                                                                                                                  Best of 73's Dave
                                                                                                                            Meet you on 17m or 40m
                                                                                                                                    Mike KD2DYY
Logged
GM8UPI
Member

Posts: 84




Ignore
« Reply #2 on: September 07, 2013, 12:11:23 AM »

Hi Mike. Thanks for coming back on this. Yes, I have been studying Ken's web site. I have used his services when refurbishing my TS-520, a lovely classic and the original "best of bunch" in my opinion, of the first Hybrids! Lovely rig, and I will never part with it until SK arrives! LOL.....
Certainly would be interested in the Kenwood Group link, if you can give me a stear on this.
Maybe catch you on air some time during this coming winter. As my QRZ page indicates I spend most of my time these days here on the Isle of Skye, Scottish Western Islands. Lovely and remote but being a "towny" by birth, I am now loving the isolation!
73
Dave
Logged
G3RZP
Member

Posts: 4625




Ignore
« Reply #3 on: September 07, 2013, 01:11:16 AM »

Dave,

Bear in mind that you have a rig MUCH cleaner in terms of high order IMD product than anything available these days. You might need new PA tubes as well, though.

73

Peter G3RZP
Logged
GM8UPI
Member

Posts: 84




Ignore
« Reply #4 on: September 07, 2013, 01:36:44 AM »

Hi Pete. I have plenty of good spare 6146B's and driver valves, so no problem to revalve the rig.
Still wondering if the need to have mic gain fully up is norm on using these hybrids, and having to talk close to mic for correct SSB drive level. ie mid ALC scale.  Both 520 and 830 are identical in this respect, using same MC-50 mic !
Would have thought that the design would allow normal desk mic distance, ie 6-8ins, to be around 60 - 80% of mic gain setting, for full drive without overdriving anything.
Investigation continues.................
Regards
73
Dave
Logged
W8AAZ
Member

Posts: 346




Ignore
« Reply #5 on: September 07, 2013, 06:18:20 AM »

"Using the same mic".  I suppose that might make me wonder if there is some issue with the microphone itself with both radios behaving the same, unless you have found some other explanation, such as other's radios seem to have the same sort of problem. However I suspect alot of the older radios have a reduction in transmit efficiency at the very highest bands.  My experience is that only the more modern broadband solid state radios tend to be totally consistent or nearly so, in output.  I don't believe that my old FT radio can put out as much power at 10 as it does at 75 metres, regardless of how fresh the VED's are. (Eimac now refers to tubes/valves as "vacuum electron devices" Roll Eyes). 
Logged
GM8UPI
Member

Posts: 84




Ignore
« Reply #6 on: September 07, 2013, 08:11:39 AM »

Hi, thanks for responding. Not really concerned about power falling off slightly on 10. I think all tube rigs tend to do this as tubes age.
My main concern is in the use of desk mic and having to use this close-up and at full mic gain setting to produce approx 100W PEP and get the ALC registering by a small amount, powered into DL with a good, recently calibrated peak meter. (And yes, before anyone comments, I know all about how difficult it is to measure PEP on these meters!!)
The bottom line is I get great audio reports using the mic close-up, and I am looking to get same while talking 6-8inches away, and preferably, not with mic gain fully up !!
I've no reason to suspect the MC-50 and I have also tried a Shure 414B fist mic with same results.
The mic Amp circuits (3 transistors before 1st mixer) are similar but not totally identical in the 520 and 830. BTW the VOX works just fine, which tales audio signal after 1st mic amp transistor, which would indicate this stage is OK.
Will try replacing driver tube, then perhaps finals, and report back. (Neutalization being carried out of course, for finals !!!)

73


Dave
« Last Edit: September 07, 2013, 08:22:53 AM by GM8UPI » Logged
KD2DYY
Member

Posts: 45




Ignore
« Reply #7 on: September 07, 2013, 05:52:17 PM »

Dave (GM8UPI) Here is the Yahoo user group that you can join... You have to ask for permission to join but you should have no problems in that regard....

http://groups.yahoo.com/group/ts-520_820_530_830_/

Join thier site and , like I said, watch out, they WILL tear into your issues with a vengeance...
Just give then a detailed list of what you have done so far, they will dig in....
Offer to help anther member when it is YOUR chance to do so.
 This is one more example of kindred spirits helping out  one another in a wonderful hobby.
Best of luck Dave and I hope to "work" you on the bands in near future....

                                                                                                                  73's Dave.
                                                                                                                Mike KD2DYY
Logged
K8AXW
Member

Posts: 3860




Ignore
« Reply #8 on: September 07, 2013, 08:06:21 PM »

Dave:  The TS-830S is my main transceiver and has been for over 30 years. 

If you're getting 100+ watts out of it the driver and final tubes are OK. 

Normally, (which is always) my MIC control is at 5 (12 o'clock)  and the CAR control is at 2 (9 o'clock)

I use a Heil HC-4 mic element and it is within 3" of my mouth when I talk in a normal voice.

I also have the Kenwood MC-35S hand mic which is also a close talking mike....probably within an inch or two of my mouth.  Both give full output on voice peaks.

Does your mic have a Noise Cancelling and Normal switch on it?  If it's set to Noise Cancelling, then you will need to speak closer to the mic.

The very few times I've tried a desk mic I've found that I needed to be within just a few inches of the mic for full output.  This is why I prefer the boom-mic with headphones and a hand mic. I like to be able to move my head around while operating.... like to see the computer screen or do my logging, etc. 

Logged
GM8UPI
Member

Posts: 84




Ignore
« Reply #9 on: September 08, 2013, 02:32:14 AM »

The Kenwood MC-50 Desk mic, is the original mic designed for use with the TS-520, TS-830 series rigs. It has both a high and low impedance capability, with high being selected for the old hybrids. No fancy electronics etc, just a straight forward dynamic element and a built in transformer, for high, low impedance selection, made by rotating the rear connector of the stick mic by 90deg.
Difficult to see how it can be faulty, audio reports are great. Basically these mics are just like a mini speaker, with drive coil and permanent magnet. Front of mic is clean, with no obstructions etc.
Unfortunately I am "up country" for the next month or two, so do not have access to my test gear, scopes, RFVM, etc.
First move today will be to change driver tube, and see how that impacts on mic gain settings etc.
73
Dave
Logged
N8CBX
Member

Posts: 149




Ignore
« Reply #10 on: September 08, 2013, 07:00:29 AM »

I use the Shure 444 on all my Kenwood hybrids, please try one. I put all my MC50s back in the box. They have a little more gain than the MC50s
Jan N8CBX
73
Logged

Dayton Ohio - The Birthplace of Aviation
GM8UPI
Member

Posts: 84




Ignore
« Reply #11 on: September 08, 2013, 04:30:06 PM »

OK. Changed driver tube. Tried several. All worked fine, with only a v small variation in car drive setting, to produce same level of ALC. at 100w key down. Left the one in with the lowest car level setting for output. (Choice was really marginal !!)
OK. So replaced both final tubes. Quiescent current set for 60mA, only slight adjustment needed. Neutralized as per manual, Again only slight adjustment required.
Rig performing fine on all bands, with 100W+ all bands, incl 10m.
However no detectable change in SSB mic levels. IE having to speak close to mic with full mic gain set, to move the ALC to half scale !!!
Any other ideas folks Huh
73
Dave



Logged
KD2DYY
Member

Posts: 45




Ignore
« Reply #12 on: September 09, 2013, 03:47:01 PM »

Dave.................. time to get into that user group I told you about at Yahoo.( Reference my previous reply....) They DO have the expertise to help you find out the root cause of your low mic input......
I run my gain at approx 12 oclock and if I do use processor that control is set no higher than 1030.....I had my signal looked at by another Amateur that had a "'Flex7000" and he said it was just right and well withing the 3khz allowance.( about 2.3 Khz).
Now this is with Dynamic mics.... My radio did come with a Shure 444 desk mic and I have had reports that it sounded very good with that mic installed. Too bad, I like hand held PTT mics....Oh well.
Good luck Dave....... Hope you find out the solution soon.
 Fine radio you have, there. Please do NOT give up......

                                                                                                                              Mike
                                                                                                                           KD2DYY
Logged
GM8UPI
Member

Posts: 84




Ignore
« Reply #13 on: September 10, 2013, 09:07:21 AM »

OK Mike. Have joined "Yahoo Group"!!!!
Just plucking up courage to make a posting topic Undecided Undecided
73
Dave
Logged
K9TW
Member

Posts: 9




Ignore
« Reply #14 on: September 10, 2013, 05:18:10 PM »

Dave:

I agree with Jan N8CBX. I have several MC-50 and MC-60 mics and it is normal to have to talk up the MC-50 mic. People like its bass response, but if you run barefoot the Shure 444D is the mic I prefer. It is much hotter than the MC-50. Its frequency response has more communications presence so you wont get those glowing Kenwood audio reports, but you will make copy of your signal better when conditions are less than ideal or chasing DX.  I typically can run the mic gain no greater than 1100 to 1200 using the 444D and have ALC peaks about mid-scale of the black rectangular range while speaking at normal levels.

That being said you really dont know if your ALC indication is calibrated or not if the rig has passed thru other hands. The TS830 has two different ALC meter driver circuits and it requires calibrating one for S-meter function and the other for modulating the rig. If you have a Service Manual look at Step 31. It requires an accurate Audio Generator (need accurate 5mv and 10mv levels @ 1500hz) and an external wattmeter to perform this step. If you have this test gear suggest you check the cal of your ALC meter circuit. Pretty common to find them out of adjustment.

Terry K9TW

Logged
Pages: [1] 2 Next   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!