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THE AM BULLETIN BOARD => Technical Forum => Topic started by: W1KSO on February 01, 2018, 05:22:49 PM



Title: BC610E Problem
Post by: W1KSO on February 01, 2018, 05:22:49 PM
Hello
have a bc610E driving me nuts! Got this unit up and running after re-capping Osc/buffer/IPA section,
Dead and blowing fuses when acquired, Solved!
Problem: when exciter voltage is engaged, oscillator comes right on regardless of CW key being up in the 614 unit,
Seems cathode of 6v6 is hard grounded through exciter plate switch SW3 as is in the print, I cannot get the key to interrupt oscillator
unless I remove the lead from pin 3 of TS1, Seems to me the key circuit should be in series with the SW3 but it is wired in parallel
so as soon as the switch is engaged, the key/614 and  SO5 is bypassed.
Has anyone run into this?? this is a 1944 unit, Any help/wisdom will be greatly appreciated
Thanks in advance

Dick marina1950@yahoo.com


Title: Re: BC610E Problem
Post by: N8ETQ on February 01, 2018, 07:45:16 PM



Hey Dick,

    If u unplug the 614, does he unkey?
Could have been set up for RTTY.

/Dan





Title: Re: BC610E Problem
Post by: W1KSO on February 02, 2018, 03:28:35 AM
Hi Dan & Thank You for replying,

I doesn't make a difference if 614 is unplugged from SO5 of not, I tried
6V6 cathode remains grounded through TS1 # 3 through the SW3 switch, 614 connection for CW purposes are the same as
connecting the key between pins 2 and 8 of the SO5.

I didn't even think of RTTY, Do you
have any info about it they are configured?? I cannot find a complete 610E manual

Thanks

Dick


Title: Re: BC610E Problem
Post by: WBear2GCR on February 02, 2018, 08:17:50 PM
maybe:

https://bama.edebris.com/manuals/military/bc610/ (https://bama.edebris.com/manuals/military/bc610/)

www.nj7p.info/Manuals/PDFs/Military/TM%2011-826%208-Oct-52%20KG7BZ.pdf (http://www.nj7p.info/Manuals/PDFs/Military/TM%2011-826%208-Oct-52%20KG7BZ.pdf)

w5jgv.com/downloads/BC-610-E-I.pdf (http://w5jgv.com/downloads/BC-610-E-I.pdf)

www.radiomanual.info/schemi/Surplus_NATO_BC/BC-610E_sch.pdf (http://www.radiomanual.info/schemi/Surplus_NATO_BC/BC-610E_sch.pdf)

Haven't tried these... perhaps they may work/help?

                            _-_-


Title: Re: BC610E Problem
Post by: W1KSO on February 04, 2018, 05:55:07 PM
Thanks You Much!!

Dick


Title: Re: BC610E Problem
Post by: W2PFY on February 05, 2018, 02:52:18 PM
I have a BC-610D and before that I had a BC-610C. The transmitter exciter is supposed to come on when you turn that switch on. It is designed that way so you can tune the exciter for maximum grid current to the 250TH final. The transmitter is designed so that you can operate it without the BC-614 speech amplifier. One example is that you could run rtty just from the front controls of the BC-610. I run mine without a 614 strictly on AM. On my 610 near the 2A3 tubes there is a two terminal, terminal switch that provides 120 volts ac when keyed on CW or any other mode. That terminal SW is very handy for keying your antenna changeover relay if you have that terminal SW? Originally it was used to open a SW that was normally shorted across the output of the transmitters tank circuit  to keep other nearby transmitters RF out or backfeeding into the transmitter being used. If your transmitter still has that relay in there, you can remove it and use the output AC to power your change over relay. How did this relay work in a WW11 situation? Consider if you were in Headquarters in a real war situation where there may be six different BC-610's in use at the same time on six different frequencies. If that SW was not in use and there was another 610 antenna 20 feet away from your operating position and you needed to change the output tank coil? Without the shorting relay, you could get a very serious RF burn.


Title: Re: BC610E Problem
Post by: W2PFY on February 06, 2018, 10:03:46 AM
I don't know if all my blabbing above is your answer as I reread your questions? I had a situation that as soon as the BC-614 was hooked up to the transmitter, it keyed the transmitter with the exciter switch on the BC-610 being in the off position or down position. Is that what is happening with your 610? I know I fixed it.It was a shorted capacitor in the keying circuit in the BC-614. I need to study the schematic to see which cap it was?

I think the cap number C122 is the problem. In my case as soon as I hooked up the cable between the 614 & the 610, the plate replay was keyed and it turned out to be C-126 that was shorted. I just cut one end out of the circuit and it worked fine after that.



While you have it apart, if the two caps that are hooked to the primary power transformer in the 614 are still there, I would suggest you clip them out of the circuit or replace them as one day when you least expect it, they will explode with quite an alarming report. It happen to me! Those two caps on the primary are caps # c-101 & c-121. They are .01 uf caps.    


Title: Re: BC610E Problem
Post by: w4bfs on February 06, 2018, 08:11:59 PM

While you have it apart, if the two caps that are hooked to the primary power transformer in the 614 are still there, I would suggest you clip them out of the circuit or replace them as one day when you least expect it, they will explode with quite an alarming report. It happen to me! Those two caps on the primary are caps # c-101 & c-121. They are .01 uf caps.
   

blasting caps ?    sounds like old tv set with line operated doubler electrolytics     these would make shrapnel at times


Title: Re: BC610E Problem
Post by: Opcom on February 06, 2018, 09:24:51 PM

While you have it apart, if the two caps that are hooked to the primary power transformer in the 614 are still there, I would suggest you clip them out of the circuit or replace them as one day when you least expect it, they will explode with quite an alarming report. It happen to me! Those two caps on the primary are caps # c-101 & c-121. They are .01 uf caps.
   

blasting caps ?    sounds like old tv set with line operated doubler electrolytics     these would make shrapnel at times

And if lucky, the special stench of burning selenium recitifers!


Title: Re: BC610E Problem
Post by: W1KSO on May 01, 2018, 02:14:39 PM
Thank You To everyone that replied,
There are still issues with it, but on the home stretch I think
I will post the solution for all to see

Thanks
Dick

W1KSO
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands