#130

Description of problems; alignment of PA- and Driver Bias.
Part 1: • #130 Kenwood TS450S Pa...
Part 2: • #131 Kenwood TS450S Pa...
Part 3: • #132 Kenwood TS450S Pa...

[@Joe_KS1I]

Great job Stefan! I have been fooled a number of times thinking that I found the problem only to find out that it was something else. Looking forward to part two.

[@Greg-et2dp]

DL7MAJ STEFAN YOU ARE GOOD AT RESTORING VINTAGE SHORTWAVE RECEIVERS AND ALIGNMENT OF VINTAGE SHORTWAVE RECEIVERS AND RESTORING HAM

[@tlrptg]

those round connectors are called TMP connectors and some ebay sellers are asking outrageous prices for them (5 GBP !!!!) . But there is a fix for them, if the middle wire is crimped badly or if it starts not making contact just use a bit of solder and solder the tip where the crimped wire comes out. I managed to fix all TPM connectors in two of my TS430-s and a few TS450 too. regarding this TS450, don't forget to change C104 (470uF / 10V) on the IF Unit near the TDA2002 AF final amplifier to a 470uF / 16V one. This capacitor was alway leaking or was already exploded in all TS450 i ever repaired.

[@dl7majstefan753]

Tnx, the C104 was already changed by the previous owner. It had been leaking as i could see.

[@Greg-et2dp]

DL7MAJ STEFAN YOUR KZbin VIDEOS ARE AWESOME MY FRIEND

[@dl7majstefan753]

Many thanks dr Greg

[@Greg-et2dp]

DL7MAJ STEFAN THE OWNER KENWOOD ham transceiver is awesome my friend

[@rádiosantigos1958]

But it was a nice try! A very didactic video. Thanks for your explanations.

[@ATOMSHAMRADIO]

Check the filter board

[@dl7majstefan753]

Thanks, but the filters are not involved

[@Greg-et2dp]

DL7MAJ STEFAN MY HOBBIES ARE PAINTING PICTURES AND LISTENING TO SHORTWAVE AND SSB IAM THINKING ABOUT GETTING MY GRMS LICENSE

[@Greg-et2dp]

DL7MAJ STEFAN i have a vintage zenith Trans oceanic transistor shortwave receiver I want to restore it let me no ware I can get Russian germanium transistors ?

[@Justplast]

Stefan my be a Ham Radio operator :) Thay touch every think

[@dl7majstefan753]

Right! ...🙂

[@batman4e]

Sorry to say, R151 is also a typical fault of TS-850S and TS-950SDX, they both have identical TRX unit. R151 overheats because its wattage is underrated.

[@dl7majstefan753]

We are talking here about the TS450S, not 850/950S. I don´t find a R151 which could be overheated.

[@batman4e]

@@dl7majstefan753 The TRX unit in TS-450S is identical with the one in the TS-850S and TS-950SDX, it has the same part number.

[@dl7majstefan753]

@@batman4e Ah! OK, now i understand! Sorry about my slow understanding ... This R151, which i changed is 470Ohm and loaded with 7V during TX. That is app. 100mW; too much? I replaced it with a bigger one. But there is another one: R155 - same value and permanently loaded during RX, which is a longer duty cycle than TX. Didn´t change it. Maybe this overheating was the cause of the grey "powder", which is simply overheated solder.

[@darrellwofford3297]

how do you tune the receive on a Kenwood ts 450s my receive is very low enjoy all your videos I have watched Thanks

[@dl7majstefan753]

The alignment is to be done acc. to the service manual. But if there are problems, maybe the band switching diodes are faulty. Or the ATT switching is bad. Or the TX-/RX- relay needs cleaning. Or the switching between AIP ON/OFF is bad. Only some ideas from me, but a remote diagnosis is not possible for me - sorry

[@rádiosantigos1958]

I am wondering if this problem is of some capacitor that is keeping the charge longer than it should be...

[@dl7majstefan753]

Hi, but there are no capacitors involved - it´s a surprising fault - see part 2.

[@UnboxingNStuff]

When setting the HF final bias what test points do you have your multimeter connected to in order to set the correct current?

[@dl7majstefan753]

It is the total supply current from the power supply 13,8VDC. Alignment is done by change (increase) of supply current for driver and pa bias

[@UnboxingNStuff]

@@dl7majstefan753 thank you that is how I ended up adjusting the setting. I was thrown off by the service manual saying to measure at the antenna. Thank you for making these videos they are very informative.

[@mrcina22222]

👍

[@dl7majstefan753]

Tnx to all for the informations about the TMP connectors: rfconnection.com/tmp-tmp-cables-taiko-denki-connectors (tnx Bob) Found this one: www.box73.de/product_info.php?products_id=1990 (not the cheapest but OK) PS: I blocked all Links in the comments for all users due to spamming.

[@PapasDino]

The plugs are called "Taiko-Denki" or "TMP" connectors for short. They're very hard to find...I have sent you the data sheet via email. 73 - Dino KLØS

[@PapasDino]

Also, and I may have mentioned this to you before is you had another 450 on the bench...C104 is an audio coupling cap that appears to fail often. I fixed a 450 some time ago with low AF audio output and replacing that cap fixed the issue. Found that info from a web search so not original to me.

[@dl7majstefan753]

Tnx, dr Dino. I found these connectors now at a local supplier. I didn´t know the name and search engines are more stupid than me in such a case...hi. Meanwhile i found the problem - see part 2

[@PapasDino]

@@dl7majstefan753 Glad you found them locally. You really don't need the very expensive crimp tool to attach them to a piece of RG-174 or RG-316. Strip the coax back about 1" or so and separate the shields along two sides with a sharp pick so there are two braid pigtails; then fold them back along the cable. Strip the center conductor and tin then insert it into the connector and adjust the dielectric so that the inner conductor goes all the way through and the shoulders of the shield wires top out at the top of the flange channels. Once you're satisfied you can solder the inner conductor and then with a pair of pliers that will allow you to put a lot of pressure on the flange crimp the shields inside the channels; you can lightly solder them and just snip off the braid outside the channel. I was unsure this would work the first time but it's all much easier than it sounds! 73 - Dino KLØS

[@ATOMSHAMRADIO]

Or do a factory reset

[@dl7majstefan753]

Did so, didn´t help