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| ken- Need to pick your brain, but this should be easy. You have helped me several times with my TS-830S; only drawback to this radio is the inability to work split when the split is more than 2KC. Here's the question> I have the opportunity to buy a TS-570D, still in the box with a mic and DC power cord for $520 shipped to me with insurance. I was thinking about it but then I asked myself, WHAT IS A SIMPLER Kenwood HF radio I could get that would allow me to work larger splits w/o having to buy a radio with tons of bells and whistles I don't need or want? And that is the question I pose to you. What do you recommend? Take your time to answer. Thanks, Randy Hi Randy; I recommend a VFO-240 remote VFO for your 830S. That's exactly what they are made for! Best 73's, Ken Once again, you have the answer I needed to hear...have you got one for sale or a recommended source? Thanks Ken, Randy Hi again Randy; They appear pretty regularly on eBay - I don't presently have one available. There are 2 remote VFO's for the 830S, the 240, which is my favorite, and the 230, which is digital with memories. The 230 usually goes for a very stiff premium. I do not recommend the digital model because it's more prone to problems, being a very early digital design and rather complicated. The 240 is analog, identical to the VFO in the 830S, and does what it's supposed to do very well with only 4 transistors! The VFO in the picture on my home web page is a VFO-240 that works splits in style . . . 8^) Best 73's, Ken Ken- Once again, you have convinced me that what I thought was the right thing to do (VFO-230) may be exactly opposite of what would satisfy my requirement. But never having used a VFO, I need some assurances that it is as easy to use as you say. I guess there is a mechanism in the -240 that allows you to monitor/use the transmit/receive without having to spin a dial everytime you transmit.? In other words, if a DX is operating split, he may be listing on 14.225 (same freq that I would be CALLING ON), and once I made a call, the vfo would somehow be listening on say, 14.220, which is where I would be LISTENING to find out if he calls me...right? Can the TS-830S and VFO work that way so I can SET the VFO and merely xmt and then auto switch back to the VFO for listening purposes? Help me Ken...get me smart. Thanks, Randy Hi Ken, I am using the TS-830S and was wondering if I use a SB-200 amplifier would I have to make any changes to the keying line ? The SB-200 is 110 volts on the relay and did not want to damage the TS-830S. 73, Art Hi Art; The remote connector on the TS-830S has the amplifier control lines switched by RL-1-2 on the antenna relay. Those are pretty substantial contacts rated for 240VAC at a few amps. You shouldn't have any problem. Hope this helps, Best 73's, Ken Good morning Ken: I'm writing in hopes that you can help me locate what I feel is a problem in the 14VDC line in a 820 in helping a ham fix. Given: Rectifier Board shows signs of trace overheating in the area of D-8- D11 Unsoldered the red wire to the 14V terminal so I can monitor what is going on when I feed 14V in from an external source. Replaced Relay Board with a working one from my personal 820S. The problem of low voltage on the line is not C-1 and C-2 2200 mf 25VDC caps. Measuring resistance on the disconnected red 14VDC line to ground I get about 45-50 ohms. My working 820S shows zero ohms. Current draw on the 14V line, in my good 820S, is about 125 or so ma in Receive. It is in excess of 500ma on the set that has problems. Something is dragging that 14 line down. After a lot of unplugging boards and measuring voltage and current draw which is over 500 ma when I feed 6-7 volts into the 14 volt line I have decided that the CH in the 14 volt line is a very likely suspect. CH must stand for choke which is being used as a capacitance input filter on the 14V line. The same LV filter circuit is also in my 520S/SE. There is no reference in the Service Manual what the value or the location of "CH" is. If I could find it then I feel capable of eliminating it as a suspect but based upon what I've figured out the past day or so I'd wager you a good cup of your favorite Starbucks that the CH is defective with an internal short to ground. Where is it? Many thanks! 73 joe Hi Joe; You've done a nice job of tracking down the likely culprit - Now for the interesting part - I received an 820 with a similar problem a few years ago and it behaved as you describe. It turned out to be one of the leads of that choke was pinched under a screwed-down chassis partition and it had chafed and shorted to ground. The choke is behind the IF board, under that aluminum colored heat sink that is part of the DG-1 as I recall. It looks like a small filament transformer. Hope this helps, Best 73's, Ken Hi Ken, It's been a while since I last emailed you. I'm the guy that has a sick 830 and also asked if you had one for sale. I'm not looking to buy another 830 at the moment, but I do have a question related to the sick 830 I have. If C6 (the 3pf capacitor inside the final cage) was "open" and not passing any signal back to the driver tube, what would the radio do or not do? Tnx Ken, Mark Hi Mark; That cap provides negative feedback to the driver cathode. It would be the same thing as opening the negative feedback loop on an audio amp - Higher gain, more distortion. Hope this helps, Best 73's, Ken Hello Ken, I'm using an old TS-830S. Last week I made some SSTV tests and apparently I overloaded the final stage. All of a sudden smoke came out of the transceiver and when I tried to transmit again after having waited for some cooling time output power was pretty low. Having exchanged and neutralized the final tubes, output is around 90W-100W on 10m, 15m and 20m but very low on 40m (about 20W) and80m (10W). Before attempting further fixes I'd like to ask you some questions: 1. The varnish of L2, the plate choke is partly blackened. Could shorted turns of this coil be the reason for low power output on the low bands? 2. Or could this also happen, if C7, C8 or L1, you offer in FR-100 kit, are damaged? 3. Do you also ship spare parts and repair kits to Europe? Or do you have local dealers here? Thanks a lot for your help. Vy 73 from Germany Manfred Hi Manfred; Sorry to hear about the unfortunate incident with your TS-830S. When you run 100% duty cycle, you have to really cut back on the plate current. After you have repaired it, try turning the LOAD control CCW and dipping at lower output power. About 125ma max is about what you should aim for. It could be the plate choke that is causing the reduced output on 40 and 80M. They are not easy to find, and I presently don't have any. Rewinding is one possibility. You can check it out-of-circuit with a grid dip meter - If it has a shorted turn it will affect the dipper when you get near it. There's a possibility that the other choke could be damaged as well. It is part of the FR-100. A bad cap would most likely look bad on all bands, not just the low bands - Although if the plate coupling cap is now low in value, that could have that effect. I ship to Europe all the time - I get as many orders outside of the U.S. as within our borders! Those "boys down under" for instance are really into Hamming, I hear from them all the time. I hope this helps, Best 73's, Ken Hi Ken, I bought a 520S a few years ago. It works fine and then I lose audio in the speaker, after a while it comes back on and after a while it fails again. Do you have any suggestions on what the problem might be, Thank you for your time Joe Hi Joe; It's great to hear from the North Pole! It's almost always contacts that are the culprit. There are several in line with your speaker. The most common would be the headphone jack and the remote speaker jack. The easiest way to to clean them up is to spray them with some contact cleaner/lube and run a plug in and out a few times. Repeat this a few times. That may well fix it. If you don't use them very often, the contacts may develop some corrosion and will open the line to the speaker. Give it a try and let me know how it works out! Best 73's, Ken Ken, Thanks so much for your website, and info about supporting the Kenwood hybrids. It has certainly helped this newby ham and TS-830 owner. I have a question about the Dummy Load kit I had purchased from you (I hope these questions aren't too simplistic): - You say use "brass" in your article. I have "copper"; any reason I can't use copper? - When soldering the BAV21 between the red post in the lid and the center conductor plate, what is the indicator that tells me which side of the BAV21 gets soldered to the red post? - For the 1K 3W Resistors, the gold band should be on the ground, or 'lid' side, right? - When I am using this just as a dummy load, should I remove the 0.01uf disk ceramic capacitor? Or does it stay on the posts all the time? The schematic appears to say "no capaciter" as a dummy load. - I am interested in connecting wires from the posts of the dummy load, and connecting them to a digital volt meter. This will allow me to measure my power whenever I want. I plan on having the dummy load sit on the floor, so the wires would be 3-5' long to the DVM. Does this effect the calcualtions? What guage wire/type do you recommend? (stranded, solid?) I told you they would be simplistic! I appreciate the info, and look forward to returning to your site to pick up a couple more items to ensure I can hang on to this great radio for a while. Stephen Hi Stephen; Copper is fine! I said brass because it's probably easier to find. The band on the end of the diode goes to the red post. No difference - orient the resistors either way, they have no polarity. You can leave the cap in place - when it charges it's out of the circuit anyway. Wire size or length is not critical. It's DC, and your DVM has very high input impedance, so use what's handy - it will work! Hope this helps, good luck with your new dummy load, Best 73's, Ken Ken, On your rk-52 resistor package, I know where the (2) 10 ohm resistors and I know where the (2) 100 ohms go. But where does the (1) 470 ohm go, the only place I can find is R 9. Is this the correct place. Thanks Mike Hi Mike; It's the screen resistor for the finals that's on the Rectifier board, the one in series with voltage pin 210A. On the 820 it is R6 on the rectifier unit. Hope this helps, Best 73's, Ken Ken, On the HV-150B package, Is there any components in the kit that goes on the HV board itself. Sorry about all the questions, I'm just used to working on the modern equipment. But thanks to you and other hams I'm learning about these older radio's. Thanks Mike Hi Mike; The parts supplied all mount on the HV capacitors themselves. I've never seen those parts go bad, but it would be a pain to try and remove and reuse the old ones! Also, I've never found bad diodes on the HV board. The only troublesome parts are the HV electrolytics themselves - And having to replace them after 30 years is not a bad track record at all. The caps Kenwood used in general are holding up great. 73, Ken |
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